Will not start after replacing the fuel pump, the new pump is running but will not pump fuel?

The fuel pump went out, now after changing it the new pump won’t pump so the truck won’t start. I stuck the pump in the tank with no lines connected to it and it won’t even pump at all, but the pump is running. Bought 3 different new fuel pumps and none of them will pump fuel. I’ve checked the wiring and it’s correct. Before changing the pump, the truck would start but shuts off when you gave it gas, then it eventually started shutting off as soon as I would crank it up (I assume it was the loss of fuel pressure). I just don’t understand why the new pumps will run but not pump any fuel. I’ve messed with the truck for a week and can’t figure anything out.