Deploy my Node App served from my Droplet

Hello, I followed DigitalOcean’s (DO) instructions to deploy a simple “Hello World” app. Please keep in mind:

1. I got it to work in my DO droplet (I see the rendered content: mydomain.com/my-app/).
2. I understand it’s server.js code.
3. I understand it’s sites_available >default code.
4. I see another DO Community member asked this question, but there’s not solution.
5. I want my node app to be served from my droplet. Not another service like: http://my-app.dokku.me, or Hreoku The DO “Hello World” app (server.js) only renders text content. I want to use this script (server.js) to start my index.html of my Node app. Side note: my index.html contains links to app.bundle.js, app.css & an image folder. What code do I change/use (in the code, below) to start my Node (Webpack) app ?

http.createServer(function(request, response) {
response.writeHead(200, {'Content-Type': 'text/plain'});
response.end('Hello World on port 3001');
}).listen(3001, '999.999.99.999');```
Note: I've spent over 25 hours on this one aspect. 
    I've exhausted all resources I can think of. YouTube, DO, Google, ... 
Thank-you, Michael Rooney