How can you tell if your MacBookPro has a virus? (I'm running Ventura OS 13.6.4)

It's highly unlikely you'd have a virus. The system is in a protected environment. You might however have malware.

You can download the free version of Malwarebytes and scan your system for possible malware.

https://www.malwarebytes.com/

There are no known Windows-like Viruses in the wild that self replicate and affect macOS, because of the underling UNIX  Foundation and Permission Limitation. 

The Operating System resides in a Sealed and Read Only Volume that can not be opened by the User nor by Third Party Applications.

There is Malware and Adware, though it would only affect the User Account that was issued to Install It

Generally, Malware or Adware would require the User ( you ) to have purposeful granted permission to bypass the builtin Security in macOS

Security. Built right in

Mac app security enhancements

 The Built in Security  is all that is required to protect the computer.

clairefrommill valley wrote:

How can you tell if your MacBookPro has a virus? (I'm running Ventura OS 13.6.4)

Have you been downloading and installing pirate versions of expensive software?

Have you been downloading and installing software designed to access videos that are otherwise unavailable without paying?

If you answered "No" to both questions, then your Mac does not have a virus.

There are no viruses that affect macOS so just forget that idea.

Before going down that rabbit hole describe the reasons for your concern. It's always best to describe the symptoms of a problem than to assume the underlying cause.

Why do you think you might have a virus?