It's pretty easy to curate to what you like, ban communities you definitely don't like and subscribe to communities you really like while switching between all and subscribed based whether or not you want to discover new communities. You may also want to play around with what instance you use based on who they're federated with or if you want multiple accounts but that's not usually necessary.

If you're a pirate I'd recommend a lot of communities from lemmy.dbzer0.com if you're into Linux there is a fuck ton of Linux communities I'm sure you'll come across. Lemmy is full of techy and political topics mostly but there's some great memes too. I recommend the @memes@lemmy.ml personally bc it matches my personal politics more closely. If you used r/196 you may feel more at him in lemmy.blahaj.zone

Mostly you'll find that Lemmy lacks the hyper niche and fandom communities you'd find on Reddit but everything else is generally here. You can always make a niche community your self but you'll likely end up being the one posting 90% of the time unless you find some people really interested beforehand. Good luck 👍