First, a critical note: There is no such thing as a true "pop-up virus." Real viruses replicate and spread. What you actually have is adware or a browser hijacker —a potentially unwanted program (PUP) designed to flood you with ads and redirect your searches. The fake "Your computer is infected" pop-ups are the scam itself, not the virus.
Download AdwCleaner from Malwarebytes’ official website. Run it. Reset your browser. Restart your PC. If pop-ups return, you accidentally allowed notifications on a calendar or file-sharing site—repeat step #3. how to remove pop up virus
You just fixed it for free.