Creating detailed side menu from directory structure

I have seen that menus are created based on a directory presence in the pages folder. However, the top menu doesn't the sub-topics even as a drop down. My main need however is to use a side menu as it is going to be so long. And I want the side menu to show all the sub-menus too. Is it possible in grav?

The Antimatter theme does in fact handle a drop down if you enable it in the theme configuration. Learn2 theme also handles subpages, as a tree structure in the side menu. Just look at the Grav docs for an example.

Thank you. I will explore that!