phone lcd just shows white except the always on display

The Amoled is probably broken. The always on display only uses white colors and the black is just turned off pixels so that's possibly why the always on display works? You could also try and Bott it into recovery mode. ( Turn off the phone, then Hold power button, volume up button, and boxby button until you see a blue screen with an Android) then you'll want to wait until you get booted into recovery mode then use the volume keys to scroll down to factory data reset, then confirm with power button and scroll to yes. Then It will reset the phone. You will lose all the data though.