If the issue is just a failed update, you can try to restore you iPad:
First charge your iPad using a known good charger for ~30 minutes to make sure it is holding a charge.
Start iTunes on your computer.
Then turn your iPad off, connect it to your computer, press and hold home button, and while pressing home button, turn your iPad ON.
After a short while, iTunes will tell you it detected an iPad in restore mode.
You will be prompted to download and install of the latest iOS, accept and leave it undisturbed until it completes the operation.
However, you must know that if the issue is a hardware issue, due for example to a drop, liquid damage, or any other board damage inside the iPad, a restore will not fix it. Worse, it could get stuck during restore.
So can you tell for sure that there was not another incident with your iPad such as a previous repair, or drop, etc.?