Could be as simple as needing a tuneup with a new set of spark plugs.
what kind of car is it
A person pressing the gas pedal.
ANY car will stall on a proper hill if you try to bring the clutch up without any revs generated from the gas pedal.
youre lifting the clutch up to quick
Many cars require you to press the gas pedal when starting the car. It's quite normal.
You may be pressing the gas pedal too hard
If your 2003 Grand Am accelerates without pressing the gas pedal, the throttle plate may be stuck.
On cars with a carburetor you must press on the gas pedal to activate the choke, cars with fuel injection do not have a choke so this is not necessary.
clogged or bad catalitic converter
Pressing on the gas pedal sends more gas to the combustion chamber for the combustion process which sends more pressure to the engine for your car to pick up speed.
I would suspect a lack of fuel pressure, replace fuel filter, check fuel pump.
If the engine is running it is burning fuel, whether the gas pedal is pressed or not.