I have been getting pop ups stating that I have a security breach

In addition to what Kurt says:

These are probably website notifications.

You can start by going to Safari->Settings->Websites->Notifications and disallowing anything that should not be allowed. That should do it.

Just to note off the top, everything you're seeing is a lie. Do not respond to anything it's prompting you to do.

How are you seeing these. As popups in a web browser, or as notifications sliding in from the top right?