I have a 2007. Dodge ram 1500 4.7 I just changed the motor and the oil pressure drops when i stop at a stop sign or light and once i accelerate it goes back up. If anyone know what i can do to stop it

Sounds like you need to pull the oil pan to check the oil pick up tube to the sump to make sure it's installed correctly, or even there.

It is normal for your oil pressure to drop when you pull up to a stop. Rpm goes down, pressure goes down. Normal pressure is about 40 to 60 psi. It won’t wait 60 unless you’re under throttle or accelerating. I don’t know that you have a problem.