How do I establish U.S. citizenship?

Citizenship is established by verifying the applicant’s social security. In addition to individuals, corporations, partnerships, and other entities capable of holding legal title may be deemed citizens for documentation purposes. Corporations must be registered in a state or the U.S; the chief executive officer and chairman of the board of directors must be U.S. citizens, and no more than a minority of the number of directors necessary to constitute a quorum may be non-citizens. In addition, at least 75% of the stock must be vested in U.S. citizens for a coastwise or fisheries endorsement.
how do i establish us citizenship