i studing in USA, and now i doing extension my F1 visa, i heard from every one i can do it before 3 month?

Answer 1

This is from a site about united states passports

You initial stay in the United States may be valid for an initial period of 3 to 6 months. You are permitted to pursue the activities you were invited to the University to participate in. You are not permitted to be employed, or volunteer your services. Making an application to the USCIS can process extensions of your stay. The International Faculty Services Office can provide the application forms for the extension.

F-1 Students

Since the Form I-94 does not indicate an expiration date, your nonimmigrant status is valid until the end date on your Form I-20.
To maintain your status you must be enrolled in the school program indicated on the Form I-20, maintain a full course of studies and refrain from unauthorized employment. Your Immigration Advisor in ISO will give greater details about your status to you when you arrive. You must come directly to the International Faculty Services Office upon your arrival and attend orientation to initiate your enrollment.

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