I've been trying to do this but haven't yet found a way.
First, here's what I understand:
There is a categories page template, which calls a function to populate all the categories.
There is a "Categories" menu in the default menu that is based on the aforementioned categories template page.
Thus, the categories with the underline and whatever styles are presented underneath this tab.
If I create my own "Categories" tab on the header menu, then its appearance won't be the same unless I make it inherit everything from the Categories template page. However, once again, it shows all categories.
However, I want to be able to select which categories come under that menu.
What I'm thinking is, I can copy the function (haven't been able to find the right one, not sure which one it is) and make it only get() the categories I want.
For example, I am dividing my menu into a few tabs, like Autos, Categories, Jobs. I don't want Autos and Jobs to appear under Categories, because it's taking too much space and is redundant since I've divided the menu as mentioned.
Please kindly see the illustration/attachment to help in understanding what I want to do.
Please kindly let me know how I can go about this.