Facebook doesn't have a complete off switch for AI-driven suggestions, but you can significantly reduce them by adjusting your feed preferences. Go to Settings & Privacy > Settings > Feed, and look for options like "Suggested for You" or "See First." You can also try the Feed Preferences section where you'll find controls over which types of content Facebook prioritizes. The key is being specific about what you want to see more of rather than just hiding posts you don't like.
Beyond the settings, your behavior matters a lot here. The algorithm learns from what you engage with, so if you're liking, commenting, or even hovering over suggested posts, Facebook interprets that as interest. Instead, when you see a suggested post you don't want, use the three-dot menu and select "See fewer posts like this" or "Hide all from [page name]" rather than just hiding individual posts. You'll need to be consistent about this - do it every time something irrelevant pops up.
One more thing: check your ad preferences and interests under Settings > Ads. Facebook uses a lot of the same data for both ads and feed suggestions, so cleaning up what it thinks you're interested in can help. It's tedious and you'll probably never eliminate suggestions entirely, but being active about what you hide and engage with does make a real difference over time.