What's the best way to learn the ins and outs of trucking?

I'm changing careers (have been a nurse for years) and am enrolled in a CDL class that starts tomorrow.

I've wanted to drive truck for years but am clueless about how it all works. What's the best way to find out? Even simple stuff like do you sleep in the truck? or at a truck stop?

I know this is probably funny to people who do this all the time but I'm a total newbie. thanks