Because you're stepping on the gas pedal.
My 89 B2200 does this. Its like there is a dead spot in the acceleration. It is because the accelerator pump is leaking.
Driving a car is basically turning on the ignition and stepping on the gas pedal.
A 1990 Cutlass Ciera might hesitate and sputter when the gas pedal is depressed because of water in the fuel or because of damaged or dirty fuel injectors. You might also have an issue with the wiring or the distributor.
pressing on the brake pedal lightly for a short distance
When it's worn out. When it's badly adjusted. When you keep your foot lightly on the clutch pedal.
exhaust stopped up and cant breathe
It is called
Gasoline pedal/air intake pedal