if voltage is the measure of push available why it doesnt it change aceoss the paths in parallel circuits?

Answer 1

Good question. Try and think of the old comparison of the electricity to the water flowing through a hose. If we add kinks or restrictions along the main hose (in series) the pressure (push) will drop after each restriction (i.e. the voltage will drop after each resistance.) However, if we tee off the hose at the same intervals with other hoses, the pressure (push) at the end of each hose will be equal to the main hose regardless of any restrictions in the added hoses because the main hose is not changed (i.e. the voltage source will give each resistance the same "push" because the voltage source to each circuit is not changed)

Answer 2

Because the push is still the same, the current changes. Think of it as water in pipes with a single pump.