An applicant fot F-1 students must apply and get admission from a SEVP approved college or university in US and receive a form I-20 in order to apply for an F-1 visa. F-1 students must show that they are able to support themselves during their stay in the U.S., as their opportunities for legal employment are quite limited. F-2 visas are given to dependents of an F-1 student. F-2 visa-holders are prohibited from any form of compensated employment.
Citizens of Visa Waiver Program (VWP) participating countries who intend to study cannot travel on the VWP or on visitor (B) visas, except to undertake recreational study as part of a tourist visit. Students must travel to the United States with student (F-1 or M-1) visa
Except for on-campus employment of 20 hours a week or less, F-1 students are generally not permitted to work in the U.S. without prior authorization from USCIS. However, the USCIS may grant work authorization for Curricular Practical Training (CPT) and Optional Practical Training (OPT). Students are permitted to work for a total of 12 months towards practical training (e.g. internship), which can be distributed between Curricular Practical Training (CPT) and Optional Practical Training (OPT). students in STEM (Science, Technology, Engineering and Mathematics) group can legally work under OPT for 29 months. During the period of OPT, an F-1 student is not permitted to accrue more than 90 days of unemployment.