it has a free version and is available for download.
It will find any unwanted piece of software that you may have and delete it.
That said, the pop up security ads are not necessarily caused by something on your computer, there is also the possibility that the websites that you visit have them as part of their advertising.
It is also a good scam arrangement so no matter how appealing the products sounds, ignore it and move on elsewhere
Lately, I've started seeing various security ads and "clean-up" ads popping up on my desktop and I don't know how to trace their origin. If I've picked up some kind of "adware" I'd like to get rid of it, if I knew how. I realize that my Mac v10.13.1 has various utilities for monitoring activity, but I don't know how to use them for this purpose. Any help?