Hello Kaamchaiyoo, If you just want to get work authorization visas like H1b immediately to begin working, there are many hospitals in CA and TX that I know of. They might surely be in other states as well. In Dallas, TX there is Parkland hospital, in Fort Worth there's JPS and there are a bunch of others, if you search, that will sponsor you an H1B for now and will eventually sponsor Green Card. These hospitals will process your GC after you've worked for them for a year or so, if I am not wrong, because that's what I have known the case to be for some of my RN friends. So, Good Luck!