how to make what we type appear on gameobject prefab with 3d text

using c# GameObject boxbox = (GameObject)Instantiate(cube, new Vector3(Distance -3,Height,-7.7F) ,Quaternion.Euler(90, 180, 0)); this is my current instantiate code..currently i've created 3d text and make it child to the prefab game object so it will follow the gameobject wherever it goes. but i would like to make in this way that when i key in letters, it will appear on the gameobject. thru the 3d text. thanks