I created this game as an educational tool a while ago. The code is partially broken. Beware.
git clone the repo.
cd to the server/ directory, then run npm install.
Start the server by running npm start in the server/ directory.
You will also have to host the client part of the website. You can do this with Python 3 by going to the public/ directory, then running python3 -m http.server. If you do this, the game should be available at http://localhost:8000.