Configure Sub-Menus

I am new to Ghost.
I want to create a navigation which includes sub-menu items. This does not appear to be available on Ghost Pro. Could someone confirm whether it is possible and, if so, how do we do this? Or - do I need to self-host Ghost and get a developer to code it for us?

If by sub-menu, you mean something like a dropdown menu, then that’s something you need to implement yourself on Ghost(Pro) or self-hosted.

There are a number of ways to do it, but you’d need to write some custom HTML, CSS, and likely JS to accomplish it.