Interesting, but couldn't you ask this of any existing technology with years of development and realize you don't know how we arrived at a function we take for granted?
What happens when you press the accelerator on your car?
What happens when you press the accelerator on your car?
I guess a similar statement holds if you want to understand anything starting from nothing.
No single automotive engineer can answer that question to the level of detail that the original post wants to approach. A car is a collection of separately engineered mechanical devices meeting some power/torque/thermal requirements, electronic units which, to a mechanical engineer are essentially black boxes with inputs and outputs. Abstraction is in every field of engineering and it helps people reason about a complex system in terms of abstract interconnected parts, not in terms of bits, bytes, cogs or bearings.
In a similar vein, a web developer, a browser developer, a kernel developer, a network driver developer each use different levels of abstraction and paradigms in order to achieve their thing.