You can start with opening your library, we'll say pictures,
Look at the file folders tree, you'll see a libraries folder symbol, if you point at this symbol, you'll see a triangle on the left side of it, click it and it will unfold, the only real listing you need is the main pictures listing and the my pictures listing, the others can be removed, right click each additional listing and select remove from library,
Repeat for videos/ music/ documents.
Now it should show one location.
All your public folders are listed under favorites/ recently changed/ desktop.... these don't need to be removed or altered.
I'll add that you don't have to use the libraries system, just navigate directly to c username location where all of these listing are also listed in single folders view.