Please can someone explain how i use the joystick prefab for 2d.

I am making a 2d game for android and i need some help. i am trying to make my character move left and right. i have been trying to find it for 2 days and i can't seem to figure out how to do it. Also the prefab is in javascript. and im not really good with javascript either. so if anyone could help me i would be gratefull.

Please explain me in steps.