I think this decentralization and federation is what web3 is all about, without all the corporations calling everything to do with monkey pixel art that costs a million dollars “web3”
Find a few dozen people you like and start responding to their posts. Other people will see them and reply to them, and you can build up a network of people you interact with socially.
It’s not quick, but the patience helps to filter down to just the people you actually trust and want to interact with.
In addition to this on mastodon (and *key instances) you can use hashtags can be used to follow and join in on topics you wish to post about. I find that people on the fediverse tend to be a lot more responsive when you talk to them in regards to something they have posted.