well, you have bumper itself and bumper cover, or fascia.
it is very likely that you have 2 large bolts, right behind the tire wells, holding 2 long bars, that bumper is attached to, to the chassis. when those bolts are removed, and minor screws disconnected, the bumper assembly should slide out of the guides it is sitting on.
what kind of repair you need to do? a lot can be done with bumper assembly still on the car.
also, here's a quick and dirty. any local library will have Chilton repair manual. 20 cents worth of copies will give you a good guide, right?
bumper covers are very inexpensive through Certifit. but you'll have to paint it.