Can I remove a college from My Colleges / Dashboard if I’ve been accepted there? I want to make room to add in more colleges for the next round of applications but I’m too scared to click that ‘x’ 
You can. If you’ve been accepted already, they’re not going to rescind admission because of something they can’t even see.
@moongazerr once you submit an application to a college on Common App, you cannot remove that college from your list. The app will not allow it.
Exactly…that’s needed because common app limits college applications to 20.
If you are at 20 and are doing more (why?), you will need to complete the new college(s) own apps…many schools still have them. Another option could be applying via coalition app.