You can’t do that with Pihole as the ads come from the same domains, and basically need a browser extension or an app with a built in equivalent.
If you’re in the UK though, it does block the ads on All4 which was a nice surprise. It even works for the TV app.
I very recently (like last week!) stuck a new drive in my PC to run Pop!_OS, with the aim of switching over from Windows entirely if it pans out. So far I’ve only tested Steam for games, but it’s worked flawlessly for the games I’ve tried using Proton.
I’ve had a Steam Deck for some time which convinced me to make the jump. My desktop was my only Windows machine and I’d love to properly switch it to Linux.