Virus’s in my phone

You got tricked into installing a rogue calendar; your phone does not have a virus.

If your phone has iOS 13 or earlier: Go to Settings/Passwords & Accounts, look under Subscribed Calendars, tap on the offending calendar and delete it.

If your phone has iOS 14: Go to Settings/Calendar/Accounts, look under Subscribed Calendars, tap on the offending calendar and delete it.

And in the future be wary of “free” offers.

You installed calendar spam. Go into Settings and locate any active calendars you don't recognize. Delete them.

Delete the rogue calendar.

Calendar spam and not a virus.