angularfire: Error with angular 9 SSR and fire base cloud functions

I have been trying for two days now, I’m front end developer so I don’t have the require experience to use node and the cloud function

I don’t know if the following information is sufficient

so if you need any more information ask please

this is the log of fire base

Error: Cannot find module '/srv/dist/coupons/server'
    at Function.Module._resolveFilename (module.js:548:15)
    at Function.Module._load (module.js:475:25)
    at Module.require (module.js:597:17)
    at require (internal/module.js:11:18)
    at exports.universal.functions.https.onRequest (/srv/lib/index.js:5:5)
    at cloudFunction (/srv/node_modules/firebase-functions/lib/providers/https.js:49:9)
    at /worker/worker.js:783:7
    at /worker/worker.js:766:11
    at _combinedTickCallback (internal/process/next_tick.js:132:7)
    at process._tickDomainCallback (internal/process/next_tick.js:219:9)

and this is my index.ts

import * as functions from 'firebase-functions';

export const universal = functions.https.onRequest((request, response) => {
  require(`${process.cwd()}/dist/coupons/server`).app(request, response);
});

and this is sever.ts

import 'zone.js/dist/zone-node';

import { ngExpressEngine } from '@nguniversal/express-engine';
import * as express from 'express';
import { join } from 'path';

import { AppServerModule } from './src/main.server';
import { APP_BASE_HREF } from '@angular/common';
import { existsSync } from 'fs';

// The Express app is exported so that it can be used by serverless Functions.
export function app() {
  const server = express();
  const distFolder = join(process.cwd(), 'dist/coupons/browser');
  const indexHtml = existsSync(join(distFolder, 'index.original.html'))
    ? 'index.original.html'
    : 'index';

  // Our Universal express-engine (found @ https://github.com/angular/universal/tree/master/modules/express-engine)
  server.engine(
    'html',
    ngExpressEngine({
      bootstrap: AppServerModule
    })
  );

  server.set('view engine', 'html');
  server.set('views', distFolder);

  // Example Express Rest API endpoints
  // app.get('/api/**', (req, res) => { });
  // Serve static files from /browser
  server.get(
    '*.*',
    express.static(distFolder, {
      maxAge: '1y'
    })
  );

  // All regular routes use the Universal engine
  server.get('*', (req, res) => {
    res.render(indexHtml, { req, providers: [{ provide: APP_BASE_HREF, useValue: req.baseUrl }] });
  });

  return server;
}

function run() {
  const port = process.env.PORT || 4000;

  // Start up the Node server
  const server = app();
  server.listen(port, () => {
    console.log(`Node Express server listening on http://localhost:${port}`);
  });
}

// Webpack will replace 'require' with '__webpack_require__'
// '__non_webpack_require__' is a proxy to Node 'require'
// The below code is to ensure that the server is run only when not requiring the bundle.
declare const __non_webpack_require__: NodeRequire;
const mainModule = __non_webpack_require__.main;
const moduleFilename = (mainModule && mainModule.filename) || '';
if (moduleFilename === __filename || moduleFilename.includes('iisnode')) {
  run();
}

export * from './src/main.server';

i followed this guide to convert the app to SSR

Deploying your Universal application on Cloud Functions for Firebase

any help would be appreciated