Use DNS filtering. I use NextDNS which has a free tier that meets my needs. You can add popular filter lists and your browser will never even see those ads, trackers etc. Or you can use Vivaldi and Firefox of course. But DNS cuts it off before it even gets to your machine.
Alternatively, you can just host this stuff yourself and never pay. A Pihole is just DNS-filtering. There's a million guides to do this on the internet already. You can also do it more directly with some routers, I run DNS filtering on an ASUS router with the merlin third-party firmware. It's possibly the simplest thing you can host yourself. Like others have pointed out though, it isn't a replacement for uBO. They both complement each other and I would recommend both to people who are able. The one major advantage it has is being able to block some ads in mobile apps. But it cannot block as many in a browser.