Hi there!
Thanks for your query.
Did you mean the Layout bundles/page templates those are free with the SP Page Builder Pro?
Have you downloaded and installed the SP Page Builder Pro version in your Joomla site? If yes, then you already have those Layout Bundles, and you can access them right in your SP Page Builder editor panel. You can export/import them as well. Here is related documentation link:
https://www.joomshaper.com/documentation/sp-page-builder/sp-page-builder-3/how-to-tips#how-to-access-and-import-layout-bundles
https://www.joomshaper.com/documentation/sp-page-builder/sp-page-builder-4/layouts
Download is not possible, you can export them as .json file and import them in another site with similar environment.
Best Regards