McAfee and Big Sur upgrade

I had McAfee installed on my Mac Mini (late 2014) I updated the OS to Big Sur and the McAfee software did not work. I called McAfee and was on the phone with them for over an hour trying to reinstall their software. They could not get it to work and suggested I contact Apple support. If I can't get my Mac Mini to take the reinstallation is it true that the Apple software has it's own virus protection built in or should I try reinstalling somehow the previous version I had on my Mac?