How do I download the Billiard Table in this website?

Hi Karoline, unfortunately this brand does not have any BIM/CAD files for its products.
If you want to only see products that have the right files, you can do a search and use the 'Formats' filter. Here is a blank search that will show you all products with Revit files: https://www.modlar.com/search/products/format--revit/