Masto has 3 feeds Federated: everyone your server knows (public posts) Local: people on your server only (public posts) Home: All posts from people you follow There is not algoryhthm for feeds, just chronological order.

Check Federated and Local feeds for new people. Click on their profile and follow/mute/etc as you want

Also, search hashtags you are interesed in and try the same of federated and local