How can I make a thumbstick with this code? HELP

I have this code and it works fine when I attach it to the main camera, I wan’t this script to be activated if I touch a thumbstick/GUItexture… When I attach the script to a guitexture nothing happens. By the way this is mouse look script from: unifycommunity.com

here’s my code!

using UnityEngine;

[AddComponentMenu("Camera-Control/Touch Look")]
public class TouchLook : MonoBehaviour {
    public float sensitivityX = 5.0f;
    public float sensitivityY = 5.0f;
    public bool invertX = false;
    public bool invertY = false;

    void Update()
    {
        if (Input.touches.Length > 0)
        {
            if (Input.touches[0].phase == TouchPhase.Moved)
            {
                Vector2 delta = Input.touches[0].deltaPosition;
    
                float rotationZ = delta.x * sensitivityX * Time.deltaTime;
                rotationZ = invertX ? rotationZ : rotationZ * -1;
    
                float rotationX = delta.y * sensitivityY * Time.deltaTime;
                rotationX = invertY ? rotationX : rotationX * -1;

                transform.localEulerAngles += new Vector3(rotationX, rotationZ, 0);
            }
        }
    }
}

I don’t knoww what a thumbstick is, but you’ll probably need OnMouseDown and enabled = true;