If you’re considering starting a U.S.-based business, you could qualify for an E-2 treaty investor visa. This is a 2- to 5-year nonimmigrant visa, but there are no limits on the number of renewals. It allows the investor of significant capital in a U.S.- based business to live and work in the U.S. It also allows key employees of the enterprise to come to the U.S., along with the families of E-2 visa holders.
Any US citizen can sponsor a fiancé/fiancée to live in the States
Whether you're a birthright citizen or were naturalized, you can petition to bring your foreign-born fiancé(e) to the United States for the wedding. They can use a K-1 visa, as long as you intend to marry within 90 days of their entry. Once you are married, your spouse can apply for lawful permanent residence (green card status) and, eventually, citizenship.
