So i found another blank map i want to work with. But what now? how do i start making it look like professional map like the ones i posted, as specially the third one?

These may sound stupid questions, but google was no use for me when trying to find any tutorials. The style i am trying to replicate is the one in the 4th image, but with clear defined borders (how to make borders in Illustrator is another mystery i cannot solve)

please help