Why is my tab a screen black but glowing with backlight

so, about 3 months ago i went through TSA and when i got on the plane and ever since, the screen has been black but the backlight is on. since the screen still glows i have hope in fixing it. i gave up on it for a while and i wanna try fixing it again. i do not want to lose my information that is on it so i cant factory reset. i cant connect it to my pc because it has to be unlocked to allow access. i dont know what to do at this point. ive read so many articles but none seem to apply.( side note: does holding power, vol up and vol down reset or bring into recovery menu or somthing else?)