Why does the new moon receive sunlight only on the side facing away from earth?

well since the moon only face us one side when a eclipse occur the side which faceing the earth are going to be shadow because the sun is at the back of the moon which is why a eclipse occur. by the way the moon only face one side becuase the moon take the same time to orbit the earth and turns around on its own axist. the simple way to understand is that when the moon orbit the earth quater way and itself turns quater way, when it orbit the earth another quater way it turns quater way and so on so on like that, in conclution no mater what happens the moon will only facing us use one side of it face.