Does anyone know well about visa?

Question

I am an international student in U.S.. I have F-1 Visa which is student Visa, I was wondering how long I have to apply before I start working using OPT(optional practical training)?

and where is my I-20's expire date? I cannot find on my I-20

Answer 1

You can apply for a new visa when you already finish your studies to change your status.

Answer 2

Your OPT must begin within 30 days of your last day of study, and it must be specified on a new I-20 form.  Every I-20 has an expiration date:  it is in Item five on the first page.  Here is a sample:

http://www6.miami.edu/international-stud...