Chevrolet 2000 Prizm Owner's Manual page 222

Remote Fuel Door Release Lever
The cap is behind a hinged door on the driver's side of
your vehicle.
6-6
The fuel door release lever
is near the floor to the left
of the driver's seat.
While refueling, hang the cap inside the fuel door.
To remove the cap, turn it slowly to the left
(counterclockwise).