how to uninstall McAfee Antivirus pop ups

These are probably notifications that come from Safari.

To get rid of them, open Safari, click Safari > Settings in the menu bar, click the Websites tab and then click Notifications in the sidebar. In the list on the right, delete the sites that send you unwanted notifications.

If it is a Notification that was allowed to pop up in Safari, it will look like this:

Stop unwanted Notifications - Apple Community

Pop-Ups can also be blocked by Safari by going to Safari > Settings > Websites > Pop-Up Windows, and you can block Pop-Ups from specific websites and all future websites by changing the option on the bottom titled "When visiting other websites" to "Block". As 6x6 suggested, a screenshot will be useful in determining where this is coming from.

If that is not what you are seeing, then post the free EtreCheck report using the Additional Text option when posting as there is a process that is running on startup that is producing this popup. Usually this occurs from a Anit-Virus application that has been installed trying to get you to subscribe to their service by giving you these fake messages that there is a problem.

Using EtreCheck - Apple Community

Could you post a screenshot of those messages?

I followed the steps in safari, websites, notifications however on the right side there are NO notifications to delete. I keep getting the McAfee endless pop ups still