You never have to worry about your family living in dorms or anything like that. In most cases, you'll move to town and pick a place to live, just like any other civilian move. You get a housing allowance based on your location, and you can spend more or less than that, as your needs dictate. Pick an apartment or rental house, and live in it. You would never live in dorms with your family, ever. Rare locations in the military require you to live in military housing if the military housing isn't full, but even then, they are decent places--usually townhouses. Someone else can speak to whether or not they will move your family for every phase of training. (If it is considered a PCS--permanent change of station--they will move your family, but if it is just a temporary assignment, then they won't pay to move your stuff. Your family could still move to your location, but that can get complicated and the military might not pay for the move. It can get complicated, but it's more than you need to worry about right now.)