What makes electricity? Is it the heat or friction or? doesn't higher voltage reduce resistance? why is it higher if voltage "pushes" the electrons and resistance "stops" the electrons"?

Why is it the same resistance before the first resistance and before the last resistance in the same closed circuit??

If voltage is the speed of electrons passing and you measure the speed, how do you measure current? Because doesn't the length of the conductor like decides how many electrons there are? Because the electrons enters AND leaves the conductor