The most common form of formal naming a person in russian is First name+Father's name(отчество). That's how children call their teachers, employees - their boss, and generally is used overall educational institutions (profs'd call each other this way in the public etc.) and every time you adress someone who's older or honored (your friends mom, any teacher or prof, some respected bisinessman, president ....). The other polite form is first+last name, but you never CALL a person like that, you won't say "Здравствуйте, Иван Иванов", you'd say "Здравствуйте, Иван". Last name is actually used only when you're presenting smone or he is presenting himself (eg an anouncer on tv). There's no ms-mr-mrs, as you can see)

When you address to unfamiliar person not necessarily use his/her last name, be enough use formal greetings. It's more important in this case.

For the first greetings, like you said before how should I talk to unfamiliar person, I will use formal forms. And do you think I should called Russian person with his/her last name? And should I add Mr./Mrs./Miss. to their name?

I already spoke that 'Здравствуйте' mean formal greetings, as 'Hello'. And 'Привет' mean unformal greetings, as 'hi, what's up'. If you address to unfamiliar person, then you should use 'Здравствуйте', it will be politely.

I have difficulties with masculine and feminine words, and to put them in sentences. So far I have no problem with pronunciation or spelling, but only with arranging words into sentences (writing).