Recently we removed wallpaper.In doing so some of the dry wall paper came off with the wallpaper. We are now left with large areas of dry wall with the second layer of paper, gray, exposed and alot of loose edges. Along with the usual gouges from scraping to hard. I thought I heard of a primer that would fill in the gouges and level the rest. But checking the big box stores no one knows what I’m talking about. Any ideas or suggestions?