Hello,
Thanks for contacting us.
Make sure you have checked all the server requirements before the installation https://www.8theme.com/documentation/xstore/theme-installation/xstore-theme-requirements/
In case if automatic plugin installation fails, you can install them manually via your Dashboard: Plugins > Add New > Upload Plugin > Browse plugins archives. Or via FTP, by uploading and extracting the plugin zip files into wp-content/plugins folder – https://www.8theme.com/download-plugins/
Then install demo content from XStore > Import Demos.
https://www.8theme.com/documentation/xstore/theme-installation/demo-content/
Let us know the result.
Regards