If That's The First Time You'll Be Changing The Phoneline's Number, You Can Get It For Free. What You Have To Do Is Tell Them That's Your First Time Changing The Phone Number, Also Tell Them The Situation.
If The Phone Is Under Your Name: Meaning The Billing Statements Is In Your Name, You Can Do It By Yourself Through The Phone. Not In The Internet.
If The Phone Is Not Under You, Then You Need To Ask Your Brother/parents To Do It For You.
They Require:
Social Security Number