not quite sure what your getting at you mean the process of how the engine starts and what not O.o
Or you want to learn how everything works period if so i would say goto school for it.
anyways you turn the key the battery then kicks on the fuel pump on an sends power to the disturb turn the key to start and then the starter turns the engine starting the car.
http://www.youtube.com/watch?v=FfTX88Sv4I8
not the full process but its the basics lol
i would start learning about older engines first if i was you there more simple then todays engines but after a while you'll see its all pretty easy to understand. start with a chevy 350 engine and work your way to computer controlled engines used in todays cars. You could probably get a 350 for about 250 bucks or so from the junk yard. Slowly work on it and takes things apart only a few special tools you might need for it.
Valve Spring compressor
bearing puller
gear puller or steering wheel puller for the harmonic balancer
hm yea thats all i can think ya would need at the moment
just have fun and experiment if you have the money to blow lol
remember its only money