You could setup NextDNS (nextdns.io) on it and enable various DNS level filter lists (and manual lists) on your NextDNS account. Each account can have multiple profiles too, which allows you to use different profiles on different devices. This will help block ads and trackers across all apps on your device, not just on the browser.

To augment it further, you could use Firefox Focus (which comes with a built-in content blocker).