broken And switch off automatically

Vaishnavi SKR at very least you want to start with a new display. Use something like this video for the work. Displays are readily available for various cost. It'll depend on your geographic are and where you order from. While you in your phone, make sure the antennae are properly connected no corrosion etc. After you replace the display consider a reset to see if that resolves the "hanging" issues.

My phone atumatic swicth off and switch on

My phone automatically switch off and switch on