WooCommerce
To fully enjoy eCommerce features in Upscale, you have to install and activate WooCommerce plugin. If you have installed and activated the required plugins after installing the theme, WooCommerce plugin is already activated on your site. If you skip the step, navigate to Appearance > Install Plugin, select WooCommerce plugin from the list, then install and activate it.
For more detail documentation, please check WooCommerce Official Guide and WooCommerce Video Tutorials.