I think, You must learn russian alphabet and some russian words and expressions such as Hello = Здраствуйте, How do you do? - Как дела? etc. The most important and most difficult is a russian grammar, because russian is very dynamic language. Russian language haven't strict structure setneces or question such as Ebglish language: For example: English sentence: The weather is bad today=Погода плохая сегодня=Плохая погода сегодня=Сегодня плохая погода <- For 1 english sentence russian language have a 3 sentence, which absolutely identical.
I think, that grammar is a most important in Russian
Sorry if I have any mistakes. My English isn't good
