3g and 4g are the same network. They are both Hspa of some sort. The note doesn't distinguish between them. 4g LTE is different though. That is why when it connects to that you get LYE under the big 4G emblem. The manual confirms this if you download it.
You dont have to change the settings of the data network, it switches the mode depending where you are. Well if ypu want to change your network you can go to menu, wireless, mobile network, network mode