I played for the first time last night, so please bear with me. The way I read the rules, a unit may move during it’s movement phase, and then may either move again OR fire during it’s assault phase. Is this correct?

Hey, newbie here. I haven’t played minis since college (80’s), but I’m thinking of buying some of these to try. If I get 1 starter set and 1 booster pack to begin, will that be enough to field both an Allied and an Axis army? If not, what would you recommend as the minimum until I play-test it a few times. And yes I know that if I like it I’ll need bunches more, but I’m looking for the initial minimal outlay of funds. Thanks.