I do not think that clinical advanced practice nurse jobs (APN/NP) can be ever given to H1 holder as there are tons of perfectly qualified American candidates fighting for these positions. It can be different for a candidate who has some very relevant work experience but even this doesn't guarantee anything.
You won't be able to study in the US on H1 unless you want to do it in your spare time. H1 visa is given for "active workforce" only, and if holder loses his/her full-time job, he has to find a new one very quickly (I do not remember exact time but it used to be around 90 days or so) or pack bags and go home. If you enter USA with the goal of studying, you'll have to get F1 ("student visa"). It is relatively easy to get nowadays, but your ability to get job will be extremely limited while on it and so those Master's programs which require students to actually work as nurses during any period of study time won't accept you. You may be rejected by other programs because F1 holders are not required to pass full security clearance and may not be permitted to do clinicals.
I'm an immigrant myself, and that's what I know: immigration in the USA is possible but there is no quick and easy ways to do it (except to win the heart of a millionaire, maybe
). It is a journey, and it can take a decade to even get close to your goals. Do your homework and think about your career in terms of immigration - it helps. Look at other options - research, for instance. Good Luck!