Nafeon on Nostr: npub1lseg6…lyhws you can follow hashtags and there are "groups" (bots that boost ...

npub1lseg6ypj6gth83m3u7eklgpcy2asp9mwygfxnpadnh3w9mrewajqulyhws (npub1lse…yhws) you can follow hashtags and there are "groups" (bots that boost everything written to them, which is good enough): https://fedi.directory/tag/fediverse-groups/

the fedi directory might overall be a good start.

we also have lemmy and kbin, which you can contribute to even with your mastodon account and also follow topics (not sure if the latter one works well).