1994 Ford Explorer Stalling when I shift gears?

When it is put into Drive or Reverse it stalls out and stops running.

Added (1). Radiator fluid was put into it and shortly after driving it away from Auto Zone it stalled out. I managed to get it running again and down the road to my house. When I parked it in the driveway it stalled again. So testing it I started it and put it into reverse. I'm reading online that this could have to do with the RPMS? Or a dirty air intake?

Added (2). I don't know what you're asking James

Added (3). Definitely going to do that Ponderer. Will edit if anything develops from it.

You could try cleaning the MAF sensor in the intake duct. They sell MAF spray cleaner at the Autozone. Have the key off when you do this. Directions on the can. Dirty IAC is another possibility.