If you plug a microwave into an outlet that doesn't have electricity (meaning it's not connected to a power source or the power supply is turned off), nothing will happen. The microwave will not turn on or operate because it is not receiving any electrical power.
Microwave ovens require electricity to function, as they use electrical energy to generate the microwaves that heat up the food. When you plug the microwave into an outlet that is not supplying power, there is no electrical current flowing into the microwave, and thus, it won't start or work in any way.
To operate a microwave, you need to make sure it is plugged into a functioning electrical outlet with power supplied to it. Always ensure that the outlet and the power cord of the microwave are in good condition and that you follow the safety guidelines provided by the manufacturer to prevent any electrical hazards.