What are the visa & residency requirements in Chicago?

"In order to obtain a visa to enter the United States, applicants must first submit an application to the U.S. Department of State. This application must include proof of identity, proof of financial support, and a valid passport. Once the application is approved, the applicant will receive a visa that will allow them to enter the United States. In order to apply for residency in Chicago, applicants must first obtain a valid visa. Once the visa is obtained, applicants must submit an application to the U.S. Citizenship and Immigration Services (USCIS). This application must include proof of identity, proof of financial support, and proof of legal status in the United States. Once the application is approved, the applicant will receive a green card that will allow them to live and work in the United States," mentioned another expat when asked about moving to Chicago, the United States.