I love my host family! I can’t guarantee that every host family is good, of course, but if you go to a well-vetted program, you will have a good time. Fill out the forms specifying the kind of family you want to stay with in detail; really think about what kind of person you are and what you need, so there won’t be a clash of personalities. I did that, and got well matched; my family is pretty chill and permissive, interesting to talk to, and culinarily talented. Every family has its own awesome traits and skills! Remember that anyone taking in a foreign student must be friendly to foreigners and want to help; they won’t be horrible to you!
If you know enough Russian to order in a restaurant, you’ll probably be fine in a bigger city in Russia. You aren’t supposed to speak Russian to cops if you aren’t Russian, and you’ll usually be able to find someone who can help you with things in English, except in stores/restaurants. So don’t worry if your Russian isn’t great right now—and anyway, it’ll get EXPONENTIALLY better from the first minute in country! I really recommend both studying abroad and living with a host family, and I hope you’ll be able to do it, anon!
If you have any more questions, feel free to ask!