1990 Jeep Cherokee wont run

Does the engine die even when you hold the accelerator pedal down 1/4"? Was the battery recently disconnected or run dead?

"but when I try to change to drive park"

How is "park" related to the problem?

I'm not really clear on your description, but it sounds like everything might be related to an idle speed that's too low. That is due to the disconnected battery. The Engine Computer has to relearn "minimum throttle" before it will know when it has to be in control of idle speed. To meet the conditions for the relearn to take place, drive at highway speed with the engine warmed up, then coast for at least seven seconds without touching the pedals.

By all means, throw a bunch more random parts at it! (That was sarcasm).

If the engine doesn't stall as long as you hold the accelerator pedal down 1/4", just drive it with both feet, one on the brake and one on the gas pedal. We do this all the time after disconnecting the battery rather than making our customers do this procedure.

The other symptoms are engine speed won't give you the nice "idle flare-up" to 1500 rpm at engine start-up, and the engine will tend to stall at stop signs.