Dark screen, can see display with flash light, tried few methods

Hi

my MacBook Pro is booting up to dark display, i can see the display with flash light and If connected to external display the computer works on the other screen.

i tried resetting the system management controller and also tried the PRAM reset .

I also deleted and tried reinstalling the iOS again nothing is helping?

what gives ..as far as I know there is no liquid damaged even the keys are covered with a plastic protector.