The second letter which a USA Lottery visa winner had received does not guarantee that you will receive an American visa. The second letter was sent to you to say that you are going to have the visa interview on that given date. On the interview, you will have to your educational qualification and that you have sufficient financial resources to support yourself. If you have dependants as family members who may accompany you to the U.S then you must have enough funds to support them till you find a suitable job in the USA. At the time of the interview the Consular officers may ask a USA visa lottery winner about their sponsor in the U.S.A. This is to make sure that someone will help the USA visa lottery winner once they arrive in the USA if they are issued with the required visas.
