You are encouraged to apply for your nonimmigrant student visa as soon as you have your I-20. To ensure you get an early and timely date you may apply at any time. However, a student visa may be issued no more than 120 days prior to the start date mentioned on your I-20.
For your initial entry, you may only enter the United States within 30 days of the beginning of the course of study stated on your I-20, regardless of when your visa was issued.
Pursuant to the provisions of Canada’s constitutional laws, the holder of a Canadian permanent resident visa and his/her accompanying dependants are permitted to permanently reside in Canada and earn a livelihood in any one of the ten provinces or three territories within Canada.
No. There is no visa that covers casual work. All applicants who plan to work in the United States must have an approved petition prior to their visa appointment.
No. Only your employer can sponsor you.
You may not enter the United States until 10 days prior to your initial employment start date, as noted on your Form I-797 or on your offer of employment letter.
You must pay the fee prior to departing for the United States. USCIS will not issue your green card until USCIS receives payment. However, even if you have not paid the fee, U.S. Customs and Border Protection officers will admit you, as long as you are otherwise eligible to enter.