“there are a few people there”

Even if you have a Mastodon account yourself, the content and contacts are not limited to Mastodon.

You are connected to a large part of the Fediverse from Mastodon and so you can i.e. also comment in Lemmy threads or send content to Lemmy.

Personally, however, I didn’t get on so well with Mastodon because I found the structure confusing and also missed some functions. I therefore moved my Mastodon account to Sharkey and have also been using Friendica for a long time. It also has a better thread structure and many more functions.