You need to find out yourself about major which will best suit you and your personality. Since you are coming from nursing background MPH/MSN/MD are some that come to my mind as potential majors.
On the side note, if you are single why not find some Nepali guys in US and get married. Life will be comparatively very easy this way compared to coming to US on student visa. I personally know couple Belgaum nursing graduates who took this route and are working here in US.