Related Questions:
Create a copy of a Menu Item
Copy a Menu or Menu Item
Duplicate a Menu
Procedure:
While it is possible to Clone individual Menu Items, whole Menus cannot currently be cloned.
To Clone a Menu Item:
Click Settings
Click Organization
Click Menus
Click on the Menu
Select the relevant Menu Item
Select the action button (down arrow)
Select Clone
Update the Cloned Item as needed (eg change price, moving it to another Menu)
Additional Information
Click here to upvote on the feature request to give users the ability to clone whole Menus!