Add explanation on how to understand roadmaps

[choripane]

Feature Description

It would be nice to have an explanation on how to understand roadmaps for those who've never seen/used one before. As in my case, I had to google how to understand roadmaps because it was overwhelming with information and nodes.
I believe something like a text box saying "To learn the skills for a main node, you should first check the dotted nodes connected to it" or something like that would make it much easier for beginners.