Dropdown menus in main header?

Read here – https://techblog.kjodle.net/2011/08/25/create-custom-menus-in-wordpress/
The “Arranging Items in a Custom Menu” section should help you.

Sorry but the onepage menu which is generated automatically doesn’t support drop-down menu.

Hello,
I created a menu for the home page. This contains a submenu under the link ” Success & performance.” Unfortunately, the sub-menu links are not clickable. How can I solve this?
thank you for your help
You can see it at https://www.asa-conseil-formation.com

MageeWP

If the theme does not support drop down menus why does the pro demo version have this feature in it? If you look at the demo and hover over the “PAGES” section in the header it has a drop down menu. How can we utilize this?