If the plugin has been correctly set and “Enable Quick View” field in settings dashboard is enabled, the “Quick View” button will be added to all the products of the shop page.
By clicking on the button, a modal window will open and will show main product information, as:
In the plugin settings dashboard, you can find the settings that allow you to change the style of some elements used by the plugin.
The free version also includes the shortcode to print the quick view button or link. You can read more about it on this page.