Issues like these are usually hardware-related and not much you can do except take it to a repair shop or, if you're knowledgeable about these things, try to repair it yourself
If you turn off your device and turn it back on, does the screen turn on briefly before loading the OS? If so, it's not hardware and you wouldn't need to change the screen.
If it doesn't turn on, does it 'show' any signs of life? Locking sounds, lights, anything?