This page can take you to information about all of the languages in this setting!
When you are RPing, it is helpful to use the abbreviation for languages in brackets, when it needs to be made clear which languages you are speaking. For example: [AC] "Yeah, sure, whatever," he said to Steve. Then he turned to Kevin and said [Lb] "This guy has no idea."
When choosing languages for your character, you should also decide whether their proficiency is broken, accented, or native.