[Robert Ferrer]

How do I perform a hard reset on my windows 10 mobile phone followed by a restore from backup?

[dKp1977]

Either jump to settings -> about and scroll down.. There's a button to perform a factory reset.
Or do it this way:

Power off your device, press and hold volume down. Now plug it into the wall charger (not necessarily required I think). Once it's powered on, an exclamation mark should be displayed on the screen. Now press volume down, volume up, power, volume down in succession. This will initiate the factory reset.

In case your device had automatically performed a backup or you did one manually, you can choose to restore from it upon setting up your device, once the hard reset is finished.