If you want to get the iPad home button on your iPad screen for any reason, you can turn it on via the iPad settings. You may want to add this home button on the iPad screen if you want more options ...
If your iPad touchscreen isn't working, the solution might be simple. Try restarting the iPad or cleaning and drying its screen and your fingers.
You can reset an iPad to its factory settings if you're experiencing significant problems with it or are planning to sell it or give it away.