Advanced Mac Cleaner and McAfee virus, won't leave! Help!

Need help to rid my MacBook Air of "Advanced Mac Cleaner" as well as "McAfee" virus!!

In the past a friend was successful at removing "Advanced Mac Cleaner," but recently I clicked agree to download an Adobe update, and clearly this update was not a good one, because within moments my computer began acting up and has worsened since. (bad Adobe was downloaded about 2 months ago)

What I'm noticing this time is every time I click on anything on my browser page (FireFox - because Safari is way too messed up to use anymore) it opens a new window at the top and reloads the current page as if nothing was clicked to begin with. It does this anywhere from 1-3 times before actually routing me to the place I want and then I have about 4 open windows at the top of my browser, all of which contain either "Advanced Mac Cleaner" or "McAFee" stuff all over it.

When I restart my computer, immediately "Advanced Mac Cleaner" ads pop up and begin talking to me, telling me it has noticed issues, blah blah blah... and contains "NA" all over them.

i have tried suggestions on I found on Apple Communities but either I am not deleting all of the files or not understanding? Anyone have advice that is easy enough for someone unfamiliar with all the computer lingo to follow?

Thanks a million!