How to make a Bitrix second level menu?

Question

1C-Bitrix

The menu itself has already been implemented
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What should I put in the admin panel so that the "Gallery" item has a drop-down menu?
Probably not enough information, be sure to clarify :)

Answer 1

Upd: I looked at the screenshot, you need to create a left-type menu in the gallery section, most likely.
The type of the second level menu can be viewed in the component's parameters in edit mode.
Original answer
Can you create menu types?
You need to use a separate type, eg. left for the second menu level.
Next, let's say the structure is
/catalog/
/catalog/category/
...
/about/
/about/contacts/
...
Where /catalog/ and /about/ are first level menu links.
Then in these sections you need to create a left-type menu, fill in the necessary items.
In the site template, for the bitrix:menu component, there is a parameter "menu type for other levels", specify left there.
In the template of the menu component, process new data accordingly.