- Dual boot should be ok. If and when you decide to fully switch, I'd say it's better to do a reinstall. Messing with partitions always comes with disclaimers. A bit advanced topic if you are interested: when you resize partition usually data needs to be moved, depending what you do with it, so it will wear your ssd; also you should be aware that you must install windows first, Linux second because windows doesn't really play well with others and be sure NOT to format EFI partition when installing Linux.
You have alternatives to dual boot: VMs. Run Linux on bare metal, then boot up a VM if you need something only windows can provide. Gnome has a new VM tool incoming.
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No idea for audio, but Photoshop has alternative, gimp. Wether you like it or not, it's another story (people I know really really hate that one). For digital art there is a tool called Krita that runs on kde. People really enjoy using it.
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NTFS has one thing that Linux doesn't really like - it is case insensitive. Linux normally works with case sensitive filesystems. There was recently a rant by the Linux overlord about case insensitive filesystems, so you might want to stay clear of it. It's ok to use it on a thumb drive though.
Edit: minor typing fixes
This is the key to a painless transition.