Hi Vidya. Are you wondering if Motorola would cover accidental damage on warranty? The answer is likely not. In such a case, a accidental fall, I'm not sure you'd have luck getting warranty from Motorola. The exception might be if you purchased some extended damage insurance from your phone provider or a third-party. I'm guessing not?

In this case, you probably need to opt for a repair and you'll likely need to replace what's called the digitizer. If you wanted to try it yourself, iFixit has a guide here. Or, you can visit a local repair shop. 

Hope this helped. Good luck.