How to remove viruses from iPhone

There a NO KNOWN viruses for iPhone, so there is no need for any anti-virus tools of any kind. If you got a message from some website saying your phone is infected, it isn't. That would be what is called a phishing scam, engineered to scare you to buy tools/software you don't need for a problem you don't have. Don't fall such nonsense.

Read this --> Recognize and avoid social engineering schemes including phishing messages, phony support calls, and other scams - Apple Support

You can't remove something that doesn't exist.

Why are you asking?

Unless previously jailbroken, it does not have a virus.

Perhaps if you describe the symptoms of this “virus” someone could offer advice.