Wordpress beginner, apologise if I'm misunderstanding something obvious.

I have a Wordpress.org site.
It's a list of people who offer various services. Each person offers a different combination of services, for example one person offers editing and proof reading, another offers ebook formatting and editing and so on.

I would like to set up the site so that one page has a complete list of everyone, and then you can also use a drop down menu to navigate to a page of everyone according to the service they offer, for example, if you're looking for editors, you can choose that from the drop down and the page will display all the editors on the list.

I don't know what terms to search for in order to find help on this.