1998 Pontiac Grand Am how to turn a motor manually that mig

i have a pontiac grand am se that ran hot and i let it sit up for a year the other day i went out an tried to start it the motor turned over a few times then when i tried again the starter would only click over i took the starter off and took it had it checked out and it tested out fine but when i put it on the car again it would kick in but the motor wouldn't turn over was wondering is it not turning over cause it doesn't have gas in it or is the motor locked up and if so is there anyway to turn the motor to free it up