If you want to update it:
npm install
gulp watch
This will watch for file changes and have everything compiled to ./dist. Open up ./dist/index.html in your browser to view it (or in vscode, right click ./dist/index.html > "Open with Live Server" to get auto-refresh on changes in the browser)
All the files are in the ./src directory - it's simple HTML and SASS.
If you're wanting to deploy - we use gulp-gh-pages to deploy the contents of ./dist to a gh-pages branch so that Github will host it.
Simply run gulp deploy and follow the instructions - it will deploy to your origin.