88 GMC 350 wants to crank but can't without help

88 GMC 350 fueling injection. Turns over and and dies. If I give it gas it’ll run sometimes it’ll crank fine. But when it goes to crank and dies I just hit the gas and she fires up. Runs fine after startup

We have a problem with terminology.

Cranking is when the starter is running (cranking) but the engine has not “caught”. You just hear a whirr-whirr sound.

“Turning over” is the same as cranking.

I think you mean your car cranks, then starts but then dies.

Cleaning the throttle body would be a good place to start. Of course if it’s been 50,000 miles since the last tune up plugs,wires, cap and rotor need replacing as do fuel and air filters.

Sounds a little like the fuel rail pressure is leaking down when the truck is off. So check valve in the fuel pump or leaking injectors or bad fuel pressure regulator. Pressure test it first. Watch the area under the injectors after shut-off to see if it leaks there. The regulator is inside the throttle body, if I remember correctly. They are available as rebuilt units for reasonable money and easy access. The pump, not so easy.