Installing required plugins
Nexgen requires a set of core and additional plugins. After installing and activating the theme you will see notifications at the top recommending the installation of the required plug-ins. This is important for you to make the most of all available resources
A plugin is an additional component that offers functionality and features beyond a typical WordPress installation. Without them, most of its functionality is not available.
You can follow the notification instructions at the top of the page or go to Appearance » Install Plugins. Just select all plugins, install and activate.
After installing the required plugins, all the theme’s features will be available.