@_elena The instance you join largely defines your experience here as they each have their own flavour and differing levels of moderation (some more, some less). You can try different ones until you get a good fit.
I'm lucky that I landed on one that works well for me - they block servers with worrisome content, I can see posts from thousands of other instances, it has a very large character/word limit for posts, and attracts a lot of people with overlapping interests.
Mastodon doesn't work as smoothly as as big name social media platforms. But if you get confused and post a question, people jump in with advice and tips. There is a bit of a learning curve (as every new endeavour has), and the people who stick with it don't mind that.
There are also volunteers who offer help and it's worth following them as they often post tips.
The volunteer culture throughout Mastodon and the Fediverse is what makes it all a great experience.
I've found a great community here. As a science writer, I've encountered and conversed with people with all sorts of expertise in sci-med-tech -- and have found leads for multiple stories I've written. Also, lots of artists who post wonderful artwork and photos. And, other writers.
Once you learn to do things like use hashtags and follow hashtags, you can 'find your people'. There are also directories out there to help you find instances to join that focus on an area of interest. Switching to another instance is easy too.