What follows, covers several Types of unless Applications including Third Party Security Software, which include Norton Antivirus.
Part 1 of 2
Once this type of software is installed. Norton 360 AV Software
You can spend hours or days hunting down all the bits and pieces of this software and never really get it all off the computer
Start Over from Scratch
For Apple Silicon computer >> Use Disk Utility to erase a Mac with Apple silicon.
For Apple Intel computers >> Use Disk Utility to erase an Intel-based Mac followed by How to reinstall macOS
Always make a Time Machine Backup before proceeding
If going this route - I suggest Not using Startup Assist to migrate everything back.
This will probably Re-Introduce ( Norton 360 AV Software ) back into the Operating System
Part 2 of 2
Third Party Security Software
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 cannot be opened by the User nor by Third Party Applications.
The Only thing this Antivirus software is protecting is the Bank Account of the Developers and for zero return to the User aside from the problems this software creates.
Security. Built right in
Mac app security enhancements
The Built in Security is all that is required to protect the computer.
Protecting against malware in macOS