About my h4 status to f1

I got admission one of the university in us .After getting admission i got married and now i have h4 visa now my question is i going to us on h4 visa after going to us can i join my master with the admision i got before marriage .And is there any possibility after joining my master can i switch my h4 to f1 visa with out going to india and how many days it will take to switch from h4 to f1