If your immigration application is missing important information or documents, USCIS will not immediately deny your application. Instead, USCIS will first mail you a Request for Evidence (RFE). The purpose of the RFE is to notify you of the defect in your application and give you an opportunity to correct the problem. If you timely respond to the RFE and provide all the information or documents that USCIS requests, USCIS will continue to process your application. If you do not, then USCIS can deny your application.
If, at the time you enter the U.S. on a tourist visa, you intend to immigrate to the U.S., you may be ineligible to receive a green card. However, if, at the time you enter the U.S. on a tourist visa, you fully intended to timely depart from the U.S. and decided to immigrate only after entering the U.S., you may be eligible to receive a green card.