1997 Chevy Lumina serpentine belt

There is a serpentine belt tensioner that is spring loaded. Using a socket and ratchet, you should be able to get a grip on the pulley portion of the tensioner and pivot it to release the pressure. With the pressure releived, the belt can be removed and gently return the tenioner pulley bak to a relaxed position. The pulley may take a 3/8" drive instead of a socket, just look and see.