Best way to organize categories

I’m a newbie to WP, so I’m trying to figure the best way to organize this. I want to be able to use WP as an organizational tools for a series of musicians. Each musician has their own set of sublinks like Tour Dates, Audio Files, Bio, etc. What I’d like to do is have each one of these be a subcategory for the artist. Simple enough. So I go to the Manage tab and add new categories and sub-categories. Again, no problem here. Pretty easy.

However, here’s where things get confusing to me. Each sub-category has it’s own ID number and what I’d really like to have instead is that there’s a main ID number for the artist and then an ID number for each sub-category than can relate to the main category so the sub-category’s ID is always the same for each artist. In other words, the Bio is always ID#!, Audio is ID#2 and so on. So that I can create a series of buttons in the content div that always stay the same since they are just looking for ID#’s for the sub-category since we’re already in the main category. So instead of https://www.yoursite.com/?cat=456 instead is could be let’s say https://www.yoursite.com/?cat=2+subcat=1 or something like that. Hopefully I’m making some sense here since I’m really a designer and not necessarily a programmer. Is this possible with or without a plugin? Any guidance would be greatly appreciated.