adding return to menu in pause mene

Questions & Answers
1

I want to add a keycode ( prefer shift key) to my pause menu to send you back main menu

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class Pause : MonoBehaviour
{
    [SerializeField] private GameObject pauseMenuUI;

    [SerializeField] private bool isPaused;

    private void Update()
    {
        if (Input.GetKeyDown(KeyCode.Escape))
        {
            isPaused = !isPaused;
        }

        if (isPaused)
        {
            ActivateMenu();
        }

        else
        {
            DeactivateMenu();
        }
    }

    void ActivateMenu()
    {
        Time.timeScale = 0;
        pauseMenuUI.SetActive(true);
    }

    void DeactivateMenu()
    {
        Time.timeScale = 1;
        pauseMenuUI.SetActive(false);
    }

}
2

It depends where is your main menu.
I have Main menu as separate scene therefore calling

if (Input.GetKeyDown(KeyCode.Shift))
{
       MainMenu()
}

void MainMenu()
{
        Time.timeScale = 1f;
        SceneManager.LoadScene("MainMenu");
}