My screen is cracked, what piece of the phone should I replace?

I play soccer with my phone almost everyday and, logically, it has fallen a few times in the process. The phone works perfectly, its functioning is remarkable, but like I said, the screen is deeply cracked, you can even see little parts of the LCD display in some areas of the phone.

As I am a normal phone user, I barely know the parts of my phone. I have seen on the internet prices from 30$ to 200$ but I'm not sure at all which one should I pick.

The question is, which exact part should I buy to fix the screen of my phone? How much should it cost so I get what I'm looking for and a good result? I also would like to know why is there such a difference between prices, is it because of the quality of the product or is it something else?