Follow a lot of people to fill up your feed. Be generous with it, and if someone you followed continuously posts something you're not interested in, you can just unfollow, or put up a filter so those posts from that person do not show up.

There's also a feature to follow hashtags so they appear in your home feed, so just search hashtags of things you find interesting. That's a good way to find new people to follow as well! Advanced web view also allows you to make feeds for specific hashtags or hashtag combinations for even more control.

And if you happen to find an instance catered to your specific interests, you can make an account there, and you can even migrate an existing account so your followers come with. Chances are the local feed will be filled up with content you enjoy on such an instance.

And if you want to help your followers discover similar people, be sure to boost content you enjoy.

On Mastodon, you are in control of your feeds. Even on the federated timeline, to an extent (as filters work there as well).