Site Navigation

I am switching a static site over to WordPress for ease of use. The site is very hierarchical, there are several topics then several items under each topic.

https://www.allachprocelain.com

If I just use pages for each item then set each items page as a child of the topics page I would have a “pages” widget a mile long.

Is there anyway to have the pages widget only show the parent pages with the option to expand and view the children?

Or is there a plugin that would create a new widget that would display the users current location on the site.

If you go to the current site you will see what I am talking about. I am sorry I know its kind of hard to understand what I am getting at here. I basically want to replicate navigation of the current site.