'98 Olds Intrigue keyless entry

As far as whether they all have keyless entry - I'm not sure..

Here's how you program in a new remote, anyway:

Important Once entering this procedure, programming the first transmitter erases all previous transmitters. You must program all transmitters. Program one vehicle at a time. One transmitter could be programmed into other vehicles that are also on program mode in close proximity.

Sit in the driver's seat. Remove the ignition key from the ignition lock cylinder. Close all vehicle doors. Press and hold unlock on the door lock switch. While holding the door lock switch in the unlock position, insert and remove the ignition key twice. Do not rotate the ignition lock cylinder. Insert the ignition key a third time leaving the key in the ignition lock cylinder. The ignition must remain in the LOCK position for the rest of the procedure. Release the door lock switch. You will hear three chimes. This chime feedback indicates that transmitter programming is active. Press and hold the lock and unlock buttons at the same time on the keyless entry transmitter for 12 seconds. You will hear two chimes. This chime feedback indicates that the transmitter has been programmed successfully. Repeat last step for the rest of the transmitters (for a total of [up to] 4 transmitters). Exit this procedure by removing the ignition key from the ignition lock cylinder.