I have a Husqvarna Viking Huskylock 936 and love it. Had a Singer before and it was ok, but like this one soooo much better. If I were you, I'd figure out what kind it is, see if there is a dealer in your area and see if they can teach you to thread and use it. Serggers are amazing and can do many things. I have made wired ribbon, rolled hems on silk blouses, table clothes and napkins, ruffles, blind hems, of course finishing seams, "seal " fabric edges for many reasons, decorative stitching and so on and so on. There are many instructional books available with wonderful projects as well. If you don't have an instruction book for your serger, I would get one of those as well.
Hope you can learn to use it and enjoy it....Don't be intimidated by it....Remeber it's a machine, somewhat like a computer, you can always turn it off and start over later.
Good Luck, Drue