Hello! Thank you for the questions. This is the shortcode we are using in our example page for the vertical menu:
[intense_menu name="Main" icon_after="chevron-down"]
When you register a menu location within a theme, you provide both a location (key) and a description. If you want to show the menu specified for a given theme location, you would use the location name (key) in this field. You can find out more about registering menus here:
https://codex.wordpress.org/Function_Reference/register_nav_menu
If you are looking for the locations defined by your theme, you should be able to find them by searching the theme code for this function.