7th Gen Ipad Black Screen after Update

I got a completely working 7th gen ipad (good as new, no issue) and i tried to update it and i got a non-functional ipad totally black screen unresponsive tried everything like the press and hold the top and homescreen button. No logo, no sound. Tried to charge it for a whole day still no changes and I tried to use a powerbank to charge it but it seems like doesnt consume the power from the powerbank.

Can someone help me with this? I really don't know what to do. This is where I study and can't afford to buy a new one😞