Turn on Airplane mode for 30 seconds after that Turn it off it will be fixed if your issue wasn't fixed Try to flash a new firmware of your device.

Try to reinstall Windows it will be Fixed.

If you have forgotten your password turn off your phone after it turned off hold Volume Up +Home Button+Power button together , free them after seeing a New page , In that page With volume up and down go Up and Down and With Power button Confirm it. Come down to Factory data reset And press power button for confirmation and then come down on yes answer and Press Power button. (1) Be aware that All of Your data on your phone will be deleted.

If the Phone Turn on but Your Screen is black and shows nothing it's probably your Screen Has been been broken and burned and you have to change it.