A good way to discover interesting posts on here is to follow hashtags. When you do this, posts with the tags will start showing up in your timeline even from accounts you don't follow.

To follow a hashtag, just search for the hashtag and then click the "Follow" button.

To check which tags you're following go to your profile and select the "followed hashtags" or # options.

This works on the web interface and most apps.

Lots more info about hashtag following:

➡️ https://fedi.tips/how-do-i-follow-hashtags-on-mastodon-and-the-fediverse/