You'll first want to make sure that you have Node.js set up on your computer.
Next, run npm install to set up all the dependencies.
You can then run npm start to start the server, and visit http://localhost:8000/ in your browser.
The current example data can be seen at http://localhost:8000/cat/Hopper.
This project is using nodemon, so you can make changes to the files while the server is running, and they'll be available as soon as you refresh the page.