UNITY: Play ingame statistics?

Okay, I am making my game a somewhat puzzle fps. Like portal, but different. So I want it to give my player statistics for stuff it does. For an example, lets say this. " [Your player name] has got [Amount of bullet damage here] hit damage!" Is there anyone that knows this? And lets just for now say the object is, a, cube.

you an uses GUI window, then create a text, and put there your variable, which contains the damage.