Question about dog training please help which obedience class do i take her to basic or intermediate?

My dog she knows how to sit and crawl and rollover but i can’t get her to stay or lay i want to take her to training but should i do the basic class or the intermediate and why?

What are the basics of dog training? Rescue dog with training already? please read whole question?

I want to get a dog from the Humane Society and will opt towards an easily trainable dog and/or one who is already trained. If he is already trained, what will I personally have to do to so he responds to me? Also, what exactly are the things I would train him? Basically, if he listens to me and can understand the commands, he will be able to understand most of what I want him to do, right?