How do serious relationships work?

My girlfriend and I are getting serious but I'm not typically from the American culture, but I will end up marrying her. I'm still in college but what do I expect in the future? Like do we get a house together after college? An apartment? Do i go to her family for christmas and thanksgiving? Do we get married and then have a house? Or have a kid and then get married? Like what is the normal storyline between a couple? What happens with serious relationships? I've seen movies where they move into an apt, and then get married and then move into a house...is this how its supposed to be? I'm not trying to follow anything I just want a headsup for the future. (PEOPLE WITH EXPERIENCE ARE REALLY GOING TO HELP!! ESPECIALLY MARRIED COUPLES)