How to fix touchscreen?

I have a 7 year old TOSHIBA tablet, not sure exactly what type. It has been working fine up until now, it has just been a bit slow. All of a sudden, the screen stopped working. It isn’t shattered or cracked, and it isn’t completely unresponsive. It clicks things by itself and most of the time doesn’t let you click anything. I tried calibrating it, restarting it, and knocking on the corners of the tablet, none of which seemed to work. The last time it was dropped was 4 days before it stopped working, so I don’t know if that is why it is broken or not. Any suggestions on how to fix it?