Hello there,

Thanks for contacting with us. The "Cannot find Joomla XML setup file" usually means you are trying to install an extension that wasn't designed for the version of Joomla you are installing to. Quickstart must be installed like Joomla step by step, all was explained in the documentation. https://www.joomshaper.com/blog/how-to-install-a-quickstart-package-of-a-joomla-template

-Regards