My router is infected

I think I’ve finally cleared out all the malware, which took forever since once you lose that technical edge, it's hard to get back. I've come to the conclusion that my router is compromised. It seems like code is being injected into absolutely everything I download. I have no clue if it arrived that way or if someone breached it later, but I could really use some advice on next steps. I'm currently using Xfinity.

What does it actually mean when people say a router is "infected" and that it's "injecting itself into everything living"?

Sent from my Android device

so I’m basically just talking nonsense here 🤦

can I get the key