Your OS doesn't matter. Printers are dumb and only understand Gcode, which is basically a series of steps to follow for printing your part (move the head this amount in that direction while extruding that much etc.). Producing that code is the slicer's job. What you want is a slicer that works perfectly on Linux. And good news, all open-source slicers work perfectly on Linux. What you need tho is a slicer that includes your printer's profile.

Try Cura or Prusaslicer (available as Flatpaks) or Orcaslicer (Appimage for now but will move to Flatpak eventually).

Most slicer software is cross platform, free and open source. The biggest ones are PrusaSlicer, Cura and OrcaSlicer. You can use all of these with lots of different brands of printers. Creality's own slicer used to just be a slightly modified version of Cura (Not sure if their new "Creality Print" software is, but it doesn't matter, you're rarely tied to any specific software, at least with FDM printers). Bambu Lab Studio is not available for Linux, but OrcaSlicer is, and as far as I know it's just an open source community edition of Studio.

In other words, you'll have plenty of options on Linux.

Get whatever printer fits your budget and needs. You don't have to have a prusa printer to use prusa slicer, and even if you don't want to use prusa slicer; Cura, super slicer, and orca slicer all work on Linux natively as well. You shouldn't have a problem with slicing software at all.

Also, as a tip, whatever printer you buy probably comes with an installer for a proprietary fork of (an old version of) one of the main slicers. Skip it. Go download Cura or prusa slicer and there will likely be profiles available during initial setup for your exact printer. Definitely if you stick to the bigger, well-known brands.

The printer is more or less separate from your PC. As several others have pointed out, you need the slicer software to create, using your PC, the file that you feed into your printer. What software your printer is running makes no difference.

The Ender 3 is the printer I recommend new users get. It's open source hardware and firmware, the devices can be found for as little as $20 sometimes. Bambu Studio, UltiMaker Cura, and PrusaSlicer, and probably loads more are all awesome slicer software that is compatible with a LARGE number of 3D printers.

Bambu labs all the way. Unless you want your hobby to become printer maintenance.

The printer doesn’t really matter. The slicer is what is os specific and most any slicer will work with Linux these days. It’s easier if you find a slicer with a premade profile for your printer but not a big deal. I’ve used prusa slicer for years with my printers (creality, voron, biqu, elegoo). Find a printer that’s in your budget and meets your needs then see what slicers have a profile for that. For modern printers klipper is a big plus. I just got a kobra 3 and it’s a decent machine. My ender 5 has been a workhorse but there are better printers these days. I don’t know enough about bamboo labs but they seem to be the new fad (well… sorta new now).

Bambu Lab makes some affordable printers that work practically right out of the box - great for beginners, but not at the expense of being able to dig down and tweak everything should you so wish. Its slicer is available for Linux.

saw the repo is 3yo without updates

that's because too many chinese companies work like this: "ooooh there's a new toy!!" and launch a slightly different model after a few weeks, discontinuing the older ones

because their firmware is just kanged marlin, it's possible to build&install the latest and greatest: https://marlinfw.org/docs/basics/install.html

Slicers for FDM are open source and lots of forks. The built-in printer profiles vary a lot but can be created from scratch. You can find lots online to use as examples too. I currently use Cura, Prusaslicer, and Orcaslicer.

I'm more interested in printing plastic than tuning/upgrading the printer itself so I recommend a printer with automatic z-offset and bed leveling. Basic maintenance tasks such as cleaning, oiling, and greasing will need to be done on occasion no matter the printer. Beyond that I've only done simple retraction tuning.

I started with Elegoo Neptune 3 Pro. Klipper firmware upgrade improved speeds a lot. It wasn't bad for a budget printer but lack of automatic z-offset can be frustrating so I replaced & gave it away to friend. Replaced it with Creality K1 which was a lot easier to get started with thanks to automatic z-offset calibration. Output quality is good but to get better would require upgrades + tuning. Been saving up to replace with Bambu Lab P1S combo so I can also do multi-color printing.

I currently do all of my 3d printing from Linux. My printer is physically connected to my server, which is running Ubuntu and has a docker container running Octoprint. The container is based on Debian. The printer itself is a crappy knock-off of the Ender 3. The only issue was identifying the port I needed to pass through to the container.. And by "issue", I mean I had to run ls -l /dev/serial/by-id and put the resulting device in the devices declaration of my docker-compose.yaml file.

My main machine is Arch and I use Prusa Slicer as an Appimage. The only issue there is that Prusa Slicer likes to SegFault while slicing some models with some settings on my system. It's not common, but it does happen. I think this is related to the Nvidia drivers; but, by using the Appimage it's just the application which crashes and I can't be arsed to spend the time to solve the issue. I also tried Cura, but ran into this bug (tl;dr: don't use Nvidia on Linux). Overall though, it just works and I don't really think about the fact that I'm on Linux.

For modeling, I personally use OpenScad, as I have all the artistic capabilities of a mortally wounded water buffalo. One of these days, I'll pretend to try to learn FreeCad, which runs just fine. Blender also runs great on Linux.

In short, so long as you aren't buying anything too proprietary, you should be just fine.

I have a prusa mk3 that I recently upgraded to mk4. They are expensive, but they are also super-reliable, they have great customer support, and they fully support 3rd party components. Not to mention the upgrades. After 3+ years as a mk3, the upgrade cost me about 700 EUR and it was like getting a new printer with modern specs.

You will save money in the long run, and a ton of nerves. Even if you are just looking to use it for a limited period of time, the resale value will be good.

You might want to double check this, but as far as I remember both the Sovol SV06 and SV08 are open source. The SV06 sounds in line with your desired budget, IF I remember correctly the open source thing. And as others have said, Cura, Prusa slicer and Orca are open source and cross platform.

Personally using an Elegoo Mars 2 with Chitubox and I had no issues with it so far

To 3d print something you need to convert a model (.stl or something else) to gcode. A slicer will do this for you. I use Cura (it's open source) and works great on Linux. Then you have to send that gcode to the printer. You can do that with micro SD card which is what I noramlly do or you can connect to the printer using USB cable and send the gcode using a slicer.

Orcaslicer runs on Linux which interfaces with almost every printer. It is a merge between Prusa and Bambu slicer

Bambu Labs is closed source but currently by far the best option for out of the box printing.

If you want open source consider the Sovol Sv08 but as a beginner this is a difficult start in the hobby. Or a Prusa printer.

Buy a bambu a1 mini, their slicer (based on prusaslicer) works great on linux and their printers are really easy to use, have good print quality and print fast.

^ if you want to print instead of thinkering with your printer

What volume of print area do you need? Any specific filament types you want to use? What sort of budget? Do you want something that just works or are you fine with tinkering?

Hardware

I mentioned in another topic that prusas solid machines, yeah they're pricey, kits are cheaper than assembled and because they're easy to service, I wouldn't even hesitate at grabbing a second hand one.

A lot of really good responses, there's a ton you can choose from there, however I'm going to suggest looking into a voron v0.2 kit as an option, it's totally open source and you own your hardware, I self sourced my v2.4 but I've seen decent reviews of the formbot kits, they're up to date with the voron project and look to include some mods in the kit as well, the v0.2 with everything you need to put together and a dragon HF hotend is just under $500 USD, the v0.2 is a 120x120x120 printer and is totally capable of printing abs (in fact all of the voron printers can have their parts printed on it afaik) they also have trident and v2 kits but they're twice the price for the larger kits. Another option would be to source a kit from a local supplier, will be a bit more expensive generally though.

I've done both, my first printer was a Mendelmax 2 kit that I had to sell unfortunately when I moved cross country, learned a lot building it so I bought a preassembled prusa as my next one. If diy and modding is your thing I 100% recommend building a kit, and even if tinkering isn't your thing you'll learn a lot about how they work by building one, but also totally get the need for something that's capable out of the box.

Software

I use SuperSlicer heavily, Ellis provides a great tuning guide and superslicer profiles for vorons, but overall I like it, it's a fork of PrusaSlicer which is itself based on Slic3r which has been around forever. I think SuperSlicer and PrusaSlicer are on flathub, but they also provide appimages. SuperSlicer has a ton of settings, PrusaSlicer has some really nice features and out of the box printer and filament profiles, also a measuring tool which is nice. I like the interface better on SuperSlicer and it has some tuning tools built in.