How to create a new cate in vertical menu
Step 1: You need to specify your header
Please go Admin -> Mage Solution (MGS) -> MGS Theme Setting -> Header, you will see
Step 2: You need to specify the Block ID of your vertical menu that is appropriate with your header
Please go Admin -> Content -> Block -> Search "Vertical"
As you can see, here is just an example.the block ID that we're mentioning is "2"
(All the blocks were auto generated when we import our static blocks into your Magento)
Step 3: You need to create a vertical menu with the ID you found, for example, the block ID is "2" so you need a vertical menu has ID = "2" as well
Please go MGS -> Mega Menu -> Manage Menu
Please note: The menu type must be "vertical"
Step 4: Now you can create items for your vertical menu
Please go MGS -> Megamenu -> Manage megamenu items -> Add item
Please note: You need to choose the proper menu