WooCommerce is an open source e-commerce plug-in for WordPress. In order to use the WooCommerce and Hoplix plugins, you must be using WordPress version 4.3 or later with WooCommerce installed in your account. The WooCommerce plugin for your WordPress can be found here.
Once installed, you can follow this article to install Hoplix in your WooCommerce shop: How do I install the Hoplix plugin for WooCommerce?