We've learned how we call different countries, nationalities and languages in Russian. 
The clip below will go through some of the stuff that we've learned and will provide you with some new words and phrases.
Note that the word Belarus "Беларусь" is the way it is pronounced in Belorusian language and what is considered to be the official name of the country these days. In Russian they used to say Belorussia - Белоруссия and this name is now considered to be obsolete
Good luck!

Countries and nationalities.