rename tiles in grid | unity3d

using System.Text.RegularExpressions;
using UnityEditor;
using UnityEngine;
using UnityEngine.UIElements;

public class EditRename : EditorWindow
{
    [MenuItem("dev/hierarchly")]
    public static void showHierEditWind()
    {
        EditRename hierWind = GetWindow<EditRename>();
        hierWind.titleContent = new GUIContent("rename tiles");
    }

    public TextField newTagTitle;

    public void CreateGUI()
    {
        VisualElement rootVisual = rootVisualElement;

        Button mainBtn = new Button();
        mainBtn.name = "renameBtn";
        mainBtn.text = "rename tiles";
        mainBtn.clicked += MainBtn_clicked;

        rootVisual.Add(mainBtn);

        Button changeTagBtn = new Button();
        changeTagBtn.name = "changeTagBtn";
        changeTagBtn.text = "change tag";
        changeTagBtn.clicked += ChangeTagBtn_clicked;;

        newTagTitle = new TextField();
        newTagTitle.value = "set title new tag";

        rootVisual.Add(newTagTitle);
        rootVisual.Add(changeTagBtn);
    }

    private void MainBtn_clicked()
    {
        GameObject[] objs = GameObject.FindGameObjectsWithTag("tile");

        for (int i = 0; i < 10; i++)
        {
            for (int j = 0; j < 10; j++)
            {
                objs[(i * 10) + j].name = string.Format("tile {0} {1}", i, j);
            }
        }
    }

    private void ChangeTagBtn_clicked()
    {
        GameObject[] objs = GameObject.FindGameObjectsWithTag("tile");

        foreach (GameObject obj in objs)
            obj.transform.GetChild(0).tag = newTagTitle.value;
    }
}