Every society has its rules. Every group within society has its own subset of rules.
While it would be wonderful if all these rules were written down somewhere, the reality is that they aren’t.
So how can you learn about them?
Watch what others are doing and learn. Learn from the good examples (and from the silly mistakes).
If you “dive in” you can easily upset other members of the community, so they’ll be less likely to want to listen to you.
If, on the other hand, you hang around a bit and watch how people interact within the community you’ll have a much better chance of success.
Watch, listen, learn.
And if you’re still not sure .. watch, listen and learn some more.
If you were building a house you’d expect it to have solid foundations. Why should your online interactions be any different?