How to Add Multiple Menus to the Header in Multi WordPress Theme?
More than one header menu
Multi allows you to add two different menus to your header and place them anywhere you want. Go to Appearance > Customize > Header > Layout and use the Main menu position and Header additional menu position options to set the display position for each one of the menus.
Set each menu’s position to left, center, or right on the top or bottom header part, or disable it.