"Code Alarm" is the brand of the alarm system. It is aftermarket usually sold in car stereo shops. If you can find the actual unit under the steering wheel area you may be able to see the model number. Once you have this you can look up the programming instructions or perhaps call the manufacturer. But if you have a stereo shop in the area they should be able to help.
1996 Ranger XLT V6 4.0 5 Speed Manual.