Check if you have already installed the SiteBuilder Module on your site (click Install if not).
The version should be at least 4.11.2 (we'd recommend updating to the latest version).
The SiteBuilder Module comes with the Free Flowbite Theme automatically.
If the download does not show as Installed after some time, try refreshing the page and trying again - it is a large package of files.
Next Steps:
You'll need to create a Page Template:
{% content-ref url="create-a-page-template.md" %} create-a-page-template.md {% endcontent-ref %}