Meta launched Your Algorithm on Facebook, letting people describe what they want more or less of in Feeds and Reels. Changes are supposed to appear in real time, with follow-up questions and buttons to gauge interest under the three-dot menu. 

Open Facebook > tap the three dots (•••) on any post or Reel > Select Your algorithm > add topics you want to see more or less of.

You can also tap Interested or Not interested on individual posts to fine-tune your feed.