The screen of laptop becomes black how to fix it

@rayyanbakht "The screen of laptop becomes balck" means to me that you have a display which then turns black. Correct? If so try this.

Once your screen goes black, use a flashlight and shine the beam at an angle against the screen. See if you can make out shadows or shapes of your desktop. Do this in a fairly dark room.

If you do see your desktop, then it is your backlight that has failed. If not, then it could be a GPU issue. Connect an external monitor and see if that turn black as well. If so, it's most likely your GPU.