add to 'Menus' ?

Hello, and thanks for the time. I’m a beginner, so this might be painfully obvious…

I’d like to use the accordion menu as the only menu on my site.

I’m currently running the Hum theme, which is a child of twenty eleven.

This is my site..

https://nicholasbivins.com

On the Portfolio page, I’ve placed the shortcode so I know the menu works, but how can I get it as my main navigation. Is there a widget/plugin/tool that can make Accordion Menu show up as an option under Appearance->Menus?

Thanks!

https://www.ads-software.com/plugins/nextend-accordion-menu/