I have a Submersible Deep Well Pump. I can have water for 10 minutes then no water for 1 to 2 hours. Then have water again. I dropped a rock down the well and we have plenty of water. Only getting 20psi- 25psi in holding tank. What could be the problem?

Your pump is behaving as though the water table has dropped. It can run for a few minutes, the water level drops, and then it takes some time for the water level to recover. It could also be a problem with the pump. How old is it and how far down is it?

Dropping a rock down the well is a poor test for water level.