Yes, you need to install WordPress first, and then you'll be able to upload and activate the ClassiPress theme (it won't work without WordPress). You may like to check out some of the
theme documentation regarding setup if you'd like to get an idea of how that part works. We don't have any trial versions of our themes available, but you can view theme information on the
ClassiPress page, including links to the front and back end demo site. If there's anything else you're not sure about, please feel free to ask here :) Thanks.