Having trouble with first time Mac App's Quit Function

Hi, I'm in the process of writing my first Mac Menu Bar app. I must include a way to quit the app by the normal [Command+Q] option. I got the below code from a YouTube video and it works on the video, but not in my app. I am also using SwiftUI.

The code's filename is ApplicationMenu.swift and is written in Swift. According to the video (which I cannot include in this message) the below example shows the menu appearing at the bottom of the window, but when I do it, it doesn't show up.

Thank you.

Here's the code:

import SwiftUI

class ApplicationMenus: NSObject
{

let menu = NSMenu()
func createMenu() -> NSMenu
  {
    let clockView = ActualClock()
    let topView = NSHostingController(rootView: clockView)
    topView.view.frame.size = CGSize(width: 255, height: 255)

    let customMenuItem = NSMenuItem()
    customMenuItem.view = topView.view
    menu.addItem(customMenuItem)
    menu.addItem(NSMenuItem.separator())

    let aboutMenuItem = NSMenuItem(title: "About",
                                   action: #selector(about),
                                   keyEquivalent: "")

    aboutMenuItem.target = self

    menu.addItem(aboutMenuItem)
    return menu
  }
  @objc func about(sender: NSMenuItem)
  {
    NSApp.orderFrontStandardAboutPanel()
  }
  @objc func support(sender: NSMenuItem)
  {
    NSApp.orderFrontStandardAboutPanel()
  }
}