I was just wondering that if you get a nose ring, or something like that, and later on in life you decide to take it out, will that hole always be there? Or will there be a scar? I read in a book that was describing a girl and it said that she had a little black hole on her nose, showing that there was a nose ring there at one time.
So will it close up? And will it leave a scar?

Yes, there will still be a small hole.