1974 Chevy Camaro stalling

If it is indeed the cylinders not firing then it's probably the distributer points or cap and rotor or something like that. Sitting for ten years is a long time. I don't know how far you want to go, but switching to an ignition system without points is a much better decision than messing with ignition points. But if you want to keep it origional this is a bad idea. An intake gasket leak and worn vaccuum lines will act like this.
Check the ignition coil and plug wires. Check or just change the plugs. Keep me posted

Get a cheap spark plug tester and test the spark. Just to rule out any spark issues. Check your plugs too. They can tell you a lot about whats happening inside of the combustion chamber. If the plugs are all carboned up them you have intake problems or the timing is off. If the car has been sitting around long enough to warrant changing the gas, then you should probably take off the whole intake and change the intake gaskets. Besides it's winter time! Give the old car a break! 34 years for a car is like 134 years in human terms. Clean that baby up for the spring--take your time and I'll help when and if I can.

Yes, they can tell you a lot. Let me know what they look like. Check them one by one and remember what cylinder they came from.