Why my screen doesn't work

It's likely that your digitizer is broken. The digitizer is what responds to your finger on the screen. This can happen after a drop (even if the screen is not cracked) and is easily repaired with a replacement screen. Sourcing one can be difficult but is not impossible. I'd suggest checking eBay or Amazon for a suitable replacement...though the cost of a replacement screen may outweigh what you paid for it.

If you decide to just replace make sure you recycle rather than throw away the tablet!