Unity MessageBox

using UnityEngine;
using UnityEngine.UI;
using TMPro;
using System;
using System.Threading.Tasks;

public class MessageBox
{
    public enum buttons
    {
        ok,
        cancel,

    }

    public readonly string Message;
    public readonly string Title;
    public readonly Action Callback;
    public readonly GameObject UIMessageBox;

    private MessageBox(string message, string title, Action callback, buttons button)
    {
        Message = message;
        Title = title;
        UIMessageBox = DisplayBox(InGameMenu.Instance.messageBoxPrefab);
        Callback = callback;
        SetText(button);
    }

    public static void Show(string errorMessage, string title)
    {
        new MessageBox(errorMessage, title, null, buttons.ok);
    }

    public static void Show(string errorMessage, string title, Action callback)
    {
        new MessageBox(errorMessage, title, callback, buttons.ok);
    }

    public static void Show(string errorMessage, string title, Action callback, buttons button)
    {
        new MessageBox(errorMessage, title, callback, button);
    }


    private GameObject DisplayBox(GameObject prefab)
    {

        return MonoBehaviour.Instantiate(prefab, InGameMenu.inGameMenuCanvas.transform);
    }

    private void SetText(buttons buttonText)
    {
        UIMessageBox.transform.GetChild(0).Find("Header").GetChild(0).GetComponent<TMP_Text>().text = Title;
        UIMessageBox.transform.GetChild(0).Find("Body").GetChild(0).GetComponent<TMP_Text>().text = Message;
        UIMessageBox.transform.GetChild(0).Find("Button").GetChild(0).GetComponent<TMP_Text>().text = buttonText.ToString();
        UIMessageBox.transform.GetChild(0).GetComponentInChildren<Button>().onClick.AddListener(delegate {
            MonoBehaviour.Destroy(UIMessageBox);
            if (Callback != null)
            {
                Callback.Invoke();
            }
        });
    }
}