Question

what is power? how do you differentiate kilowatt from kilowatt-hours?

Answer 1

The rate of doing work is power.
The unit of power is kilowatt while the unit of energy is kilowatt hours

Answer 2

The rate at which the energy is consumed or the work is done is defined as power.

A kilowatt is defined as rate of consumption of 1Kilojoule per second
But
A kilowatt-hour is defined as the amount of energy consumed at the rate of 1 kilowatt per hour.