Forever Theme adding banner ads ABOVE header

I have Forever theme on a self hosted WordPress site.
I am trying to add banner ads ABOVE my header image

my site is https://www.cataldolife.com

I have only just started editing css and php files so I need VERY SPECIFIC instructions as to where to put the code. I have tried a few things and none of them seem to work.

Also, I would like to add one to my footer – below my pst content and above the comments….where would I add this code??

Please be specific – screenshots would be ideal!!

Thanks