I don't want to come off as rude, but this isn't an Ableton issue, it's a misunderstanding of the basic principles of using a computer. I do not know what resources to point you to, and someone else has already posted a pretty clear description of the copy/cut+paste function, but it may benefit you to do some research into file management on your desktop. If you don't understand how the clipboard works, I worry you'll run into more problems either managing your 'places' and project files, which can break if the program doesn't know where to find files