What you first need is something to create a potential. This could be something electromechanical like a generator or electrochemical or it could be static charge.
Potential is measured in volts and it can be compared to force.......Its units are actually force per coulomb.
You have to have a circuit across the potential. This allows a path for electricity to flow. This even happens with static. Lighting goes between the potential of the clouds and the ground.
That is it..........Whats next and we almost got to it......Ohms law V=RI or R=V/I.