PWA custom install

Question

Good day all, I have tried visiting this page: https://web.dev/customize-install/, stackover flow questions and google pages but I still cannot get it write. I am trying to achieve three things with my PWA app:

1. Open "cache" and get files with the install event.
2. Prevent the default PWA from install using "beforeinstallprompt" listener.
3. Display a bootstrap modal with a "download" button.
4. When that button is clicked, trigger the "fetch" event which installs the app.

I am able to do 1 and 2. I am triggering my modal on main.js. I tried in the service worker but I could not. The download button on the modal also does not

index.php

    <div class="modal fade" id="myModal3" role="dialog">
    <div class="modal-dialog">
             <div class="modal-content" >
        <div class="modal-body">
                <center><p><i class="fa fa-arrow-circle-down"></i></p>
                        <h5 style="margin-top:0vh;" >Download App</h5>
            <p>Download our super cool app.
                        <div >
            <div class="wrap-login100-form-btn" >
                    <div class="login100-form-bgbtn"></div>
                <button  class="login100-form-btn"  class="AndaniDownload" id="btnDownloadAppOffline" >
                    Download </button>
            </div>

            </div>
            </center>
        </div>
                
      </div>
          </div>
  </div>
  

Main.js

$(document).ready(function(){
    $('#myModal3').modal('show');
  });

pwabuilder-sw.js

importScripts('https://storage.googleapis.com/workbox-cdn/releases/5.1.2/workbox-sw.js');

const CACHE = "pwabuilder-page";

const offlineFallbackPage = "offline.html";

self.addEventListener("message", (event) => {
  if (event.data && event.data.type === "SKIP_WAITING") {
    self.skipWaiting();
  }
});

self.addEventListener('install', async (event) => {
  event.waitUntil(
    caches.open(CACHE)
      .then((cache) => cache.add(offlineFallbackPage))
  );
});

if (workbox.navigationPreload.isSupported()) {
  workbox.navigationPreload.enable();
}

self.addEventListener('fetch', (event) => {
  if (event.request.mode === 'navigate') {
    event.respondWith((async () => {
      try {
        const preloadResp = await event.preloadResponse;

        if (preloadResp) {
          return preloadResp;
        }

        const networkResp = await fetch(event.request);
        return networkResp;
      } catch (error) {

        const cache = await caches.open(CACHE);
        const cachedResp = await cache.match(offlineFallbackPage);
        return cachedResp;
      }
    })());
  }
});

self.addEventListener('beforeinstallprompt', event => {
          
          event.preventDefault();
          var button =self.querySelector('.AndaniDownload');
          //button.removeAttribute('hidden');
          button.addEventListener('click', () => {
            
            event.prompt();
            button.setAttribute('disabled', true);
          });
        });