Convert Mouse Input to Touch Input

Hi guys. I have done a games for PC, but my target platform is Android/iOS. So the problem is how to convert Mouse Input to Touch Input. Below is my code. Can anyone help me? thanks in advance !

 using UnityEngine;
 
 using System.Collections;
 
 public class DragDrop : MonoBehaviour
 {
     private Vector3 screenPoint;
     private Vector3 offset;
 
 
     void OnMouseDown() 
     { 
         screenPoint = Camera.main.WorldToScreenPoint(gameObject.transform.position);
         
         offset = gameObject.transform.position - Camera.main.ScreenToWorldPoint(new Vector3(Input.mousePosition.x, Input.mousePosition.y, screenPoint.z));
         
         Screen.showCursor = false;
         
         
     }
     
     void OnMouseDrag() 
     { 
         Vector3 curScreenPoint = new Vector3(Input.mousePosition.x, Input.mousePosition.y, screenPoint.z);
         
         Vector3 curPosition = Camera.main.ScreenToWorldPoint(curScreenPoint) + offset;
         
         transform.position = curPosition;
         
     }
     void OnMouseUp()
         {
             Screen.showCursor=true;
     
     }
     }