I want to remove the virus on my phone

You do not have a virus on your phone.

Rather you likely have a SPAM calendar entry.

Delete spam calendars and events on iPhone - Apple Support

Did you receive a message stating that you have 13 viruses on your phone? That is a scam message. Do not reply, just delete the message and move on...

Recognize and avoid phishing messages, phony support calls, and other scams - Apple Support

No you don't have any viruses on your iPhone unless you have jailbroken it. Did you get a popup that said you have 13 viruses or is it in your calendar?

Hello

I have 13 viruses. What should I do?

Thanks