Rutager is correct. Don’t throw parts at it randomly...gets VERY expensive fast. There is one part that is worth throwing at it and it’s cheap and easy, and can cause a large range of weird electrical issues.
Ignition switch
If your AC isn’t blowing cold, listen to see if you can hear the compressor start when turning AC on and off. If compressor is coming on, have someone check refrigerant level. Small leaks are not unusual in a 20+ yr old car.