How to convert mouse input to mobile touch in unity

I am new to game development. I am try to make something like rise up. I tried to change the flowing code to make workable for mobile touchscreen unfortunately failed. can you help me how can I make flowing code for mobile?

 private Vector2 mousePos;
 private Rigidbody2D rb;
 
 private Vector2 offsetClicked;
 private Vector2 offsetReleased;
 
 private void Start () {
     rb = GetComponent<Rigidbody2D> ();
     offsetReleased = transform.position;
 }
 
 private void FixedUpdate () {
     mousePos = Camera.main.ScreenToWorldPoint (Input.mousePosition);
 
     if (Input.GetMouseButton (0)) {
         Vector2 newPos = new Vector2 (
             Mathf.Clamp(mousePos.x + offsetClicked.x, GameManager.gm.cameraEdges.w + 0.32f, GameManager.gm.cameraEdges.y - 0.32f),
             mousePos.y + offsetClicked.y
         );
 
         rb.MovePosition (newPos);
         offsetReleased = newPos - (Vector2) Camera.main.transform.position;
     } //Clicked
     else {
         Vector2 newPos = new Vector2 (
             Mathf.Clamp (Camera.main.transform.position.x + offsetReleased.x, GameManager.gm.cameraEdges.w + 0.32f, GameManager.gm.cameraEdges.y - 0.32f),
             Camera.main.transform.position.y + offsetReleased.y
         );
 
         rb.MovePosition (newPos);
         offsetClicked = newPos - mousePos;
     } //Released
 }

Above code working for mouse. Thanks you