How to make this buttons for Android?

Hey, guys. Someone knows why this didn't work on android ? XD Sorry, i'm new on Unity

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 
 public class GameController : MonoBehaviour
 {
     public string[,] tictactoeArray = new string[,]{ {"?", "?", "?"},
                                                      {"?", "?", "?"},
                                                      {"?", "?", "?"} };
     //Row 1
     public GameObject tictactoeButton00 = new GameObject();
     public GameObject tictactoeButton01 = new GameObject();
     public GameObject tictactoeButton02 = new GameObject();
     //Row 2
     public GameObject tictactoeButton10 = new GameObject();
     public GameObject tictactoeButton11 = new GameObject();
     public GameObject tictactoeButton12 = new GameObject();
     //Row 3
     public GameObject tictactoeButton20 = new GameObject();
     public GameObject tictactoeButton21 = new GameObject();
     public GameObject tictactoeButton22 = new GameObject();
 
     public GameObject X = new GameObject();
     public GameObject O = new GameObject();
 
     int round = 0;
 
     // Start is called before the first frame update
     void Start()
     {
         
     }
 
     // Update is called once per frame
     void Update()
     {
         if (Input.GetMouseButtonDown(0))
         {
             Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
             RaycastHit hit;
             if (Physics.Raycast(ray, out hit))
             {
 
             if(hit.transform.name == tictactoeButton00.name && tictactoeArray[0,0]=="?") {
                     if(round % 2 == 0)
                     {
                         tictactoeArray[0,0] = "X";
                         round++;
                         Instantiate(X, new Vector3(tictactoeButton00.transform.position.x, tictactoeButton00.transform.position.y, tictactoeButton00.transform.position.z), Quaternion.identity);
 
                     }
                     else {
                         tictactoeArray[0,0] = "O";
                         round++;
                         Instantiate(O, new Vector3(tictactoeButton00.transform.position.x, tictactoeButton00.transform.position.y, tictactoeButton00.transform.position.z), Quaternion.identity);
                     }
                 }
                     
 
             }
         }
     }
 
     private void OnMouseDown()
     {
 
     }
 }