First, you can't purge data others have collected - there is literally no way to know who has what copies. Options like Tails exist. Or "just" things like Tor

First, you can't purge data others have collected - there is literally no way to know who has what copies. Options like Tails exist. Or "just" things like Tor Browser. If you're actually as paranoid as you say, don't browse on your own devices. Don't browse in anything but anonymous browsers. Don't browse from the same places. Always use https not http (if the site(s) you want to visit support it, or course). Maybe just don't browse. I use a combination of proxies, anonymizers, ad blockers, vpns, and more for various reasons and at various times - but I also use services with logins, like convenience, etc. I'm also under no illusion that I can be fully anonymous for most things I want to do - and am ok with that.