Basic Node and Express - Serve JSON on a Specific Route

Alright, you just need one file index.js for your express. Include your code and

app.listen(3000, () => { // Make your API live
  console.log('Express server initialized');
});

And the package.json with the express package. Replit provides you a template with the prepared setup. What you need to do is to add the cors and change the routes.

Hope this helps.