The DEMO version only includes 4 pages:
https://sushicodes.com/html-an-intro-to-headers
https://sushicodes.com/html-an-intro-to-headers/category/coding.html
https://sushicodes.com/html-an-intro-to-headers/unity-tint-your-editor-while-in-playmode.html
https://sushicodes.com/html-an-intro-to-headers/sushi-game-jam-armpg-devlog-video.html

It is possible to download these free files and install them on your server, so you can test how the site works.
Visit https://www.waybackmachinedownloader.com/en/buy-wayback-machine-downloader-recover/ to buy a fully functioning site.
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