You don't need more than two or three, it's all federated, so you can access most accounts and communities from all sites on any of these sites, which is one of my favorite things about this whole thing

I've tried several and I've been here like 5 days, lol. Is there a list somewhere of all the fediverse umm...members? I just kinda jumped in and tried everything at once, but I'm curious what I missed.

Have you subscribed to cross projects already and if so how was your experience so far?

I just discovered peertube and that was wild, a big part of it being Q crazy conspiracy shit so I was turned off initially, but then I stumbled on a treasure trove of japanese comedy TV with english subtitles AND japanese (good for learning) in amazing quality!

Definitely fun exploring this, feels exciting like my introduction to the internet ages ago, discovered a lot of good and a lot of bad stuff too.