Blog Navigation

Hello everyone The topic is a ghost, I am interested in site navigation, or rather there are sections on the main page from above, for example: “home”, “about us”, “services”, “contacts”.
All these menu categories, except for “services”, do not have a subcategory. But in “services” there are subcategories: for example, “tax consulting”, “accounting services”. The question is, how do I address these subcategories to a category?

This thread has some suggestions if you are able to code: Drop down menus and Front Editing