This is a WordPress Theme starting point. It contains the absolute minimum amount of code which you need in order to start building out a WordPress website using the Site Editor.
It really is all-but completely empty and in the version you download, only the page or post content will be output on the website until you start building using the Site Editor. Start with the index.html template, which is the default which will be used if no other, more specific, template is available. An overview of the site template logic and hierarchy is available at WordPress.org.
Once you get going, you'll probably want to start using the Create Block Theme plugin to save your changes to files in a theme of your own.
Mark Howells-Mead at Say Hello GmbH, a WordPress agency in Switzerland.
Do whatever you like with this. It's shared using the Creative Commons CC0 license.