I have a pretty straight-forward question. I made a web game with NodeJS, and I can successfully play it by myself with multiple browser windows open side-by-side; however,
By default node will run on every IP address exposed by the host on which it runs. You don't need to do anything special. You already knew the server runs on a particular port. You can prove this, by using that IP address on a browser on that machine:
http://my-ip-address:port
If that didn't work, you might have your IP address wrong.