How does a fuel system for an engine work?

A fuel system starts from the tank of the fuel it has a pump that tells you the capacity, then it uses a pump to take the fuel to the filters and up the fuel lines into the fuel rail and into the inectors, if there is a problem with the fuel you can immediately tell because of the performance of the engine, there are often times when the engine doesn't want to start, you can tell if it's the fuel,if the fuel is actually reaching the engine, in the exhaust there is actually going to be smoke coming out, indicating that the combustion inside the cilynder did occur.