In your WordPress admin panel, navigate to Plugins > Add New > Upload. Choose the QuadMenu PRO plugin zip and follow the prompts to install and activate.
Appearance > Menus
If you don’t have an menu yet, go to Appearance > Menus and create one. Click the Manage Locations and assign your menu to the Primary Menu.
Header & Navigation > Primary Menu Bar
Here you’ll find a new setting called “Activate QuadMenu“. If you select this checkbox the Divi menu will be replaced with the Divi Mega Menu and a lot of new settings will be included at the bottom of the customizer panel.
QuadMenu PRO > Menu
A new metabox name QuadMenu Items will be included. If you expand this tab, you will see the advanced elements: Icon, Mega, Tabs, Search, Login and Cart.