The Shortcode Wrapper element wraps everything nested inside it between the opening and closing tags of the specified shortcode.
Add a Shortcode Wrapper element to your page from Add+ > WordPress > Shortcode Wrapper.
The Shortcode Wrapper element is most commonly used with content restriction type shortcodes. You would add the restriction shortcode to the Shortcode Wrapper and then drag all of the elements that you want to restrict access to inside of the Shortcode Wrapper.
The Shortcode Wrapper element isn't intended to be used with contact form shortcodes. If you want to add a contact form shortcode to your site (or any other non-nestable shortcode), please see the Shortcode element.