fgm24/Assets/Scripts/UI/QuitGame.cs

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

public class QuitGame : MonoBehaviour
{
    public void Quit()
    {
        Application.Quit();
    }

    private void Update()
    {
        foreach (var controller in Gamepad.all)
        {
            if (controller.squareButton.IsPressed())
            {
                Quit();
            }
        }
    }
}