https://lemmyverse.net/ in there you can search instances and communities, and If you Have an account on a y lemmy servwe you can use Its search function or if You use clients as Jerboa you can search communities with Its search function. I follow a lot of communities on Lemmy most of them are not as actives as their peers on Reddit but there are

I thought about using friendica, but I wasn’t convinced to use it. NodeBB I think it’s a good option to create a forum, but not for what I’m looking for. Thanks for the suggestion

After seeing a bit of GotoSocial I think it could be a good solution for what I need. Thanks for the recomendation