No. That’s the beauty of federation. Lemmy is not centralized like Reddit. You don’t need to be on lemmy.world to see things from other instances like lemm.ee, lemmy.ml, ani.social, etc.

Since Lemmy is not centralized, there’s no “official” community (subreddit equivalent) here. Your instance might have a meta instance community though.

There’s nothing like that here, at least not builtin. You can easily code up some bot to implement it though. !asklemmy@lemmy.world had a bot do that once when the fediverse was being spammed by some group.