Can someone explain to me why a car (manual) will cut off while driving. It seems that it only happens once the car gets warmed up after driving about 5-10 minutes. As long as my foot is on the pedal, it is fine, but once I hit the break to slow down the rpm will drop all the way to 0 and cut off. I have to constantly hit the gas and brake. I have had to throw the car into neutral at stoplights just to rev the engine to keep the car on.

For $5, change your PCV valve. Try that first before you get into the more expensive things.

It could be an idler-motor near your Plenum's air intake...or really expensive like a fuel pump.

Buy a Haynes manual. It will help troubleshoot and will even list the symptoms at the front and tell you where to start.