Unity Canvas Toggle

using UnityEngine;

public class ExitMenu : MonoBehaviour
{
    // Get the canvas game object
    public GameObject canvas;

    // Update is called every frame
    void Update()
    {
        // If the user pressed the escape key
        if (Input.GetKeyDown(KeyCode.Escape))
        {
            // If the canvas is already active
            if (canvas.activeSelf == true)
            {
                // Disable the canvas
                canvas.SetActive(false);
            }
            else
            {
                // Enable the canvas
                canvas.SetActive(true);
            }
        }
    }
}