The difference between the two is, essentially, whether or not the place is inside or outside the other place. To say something is "north of" means that it is outside of and to the north of. To say something is "northern" means that it is inside of, and towards the north. Examples: Oregon is located in the northern USA. It is found inside the north half of the USA. Canada is located in the north of the USA. It is found outside of USA, and to its north. Oregon is not in the north of the USA, because that would place it outside of the USA. Canada is not located in northern USA, because that would place it inside of the USA. Hope this helps!

yes. you can say in these ways: We are going north of Europe we are going to northern Europe