I can't do my refund by E-file so I have to sent by Mail but I want to make sure that if I sent them by mail I will get my refund
Not sure why you think you have to mail it----if you have internet access you can e-file from anywhere in the world. But if you choose to mail your tax return:
When you mail a tax return, you need to attach any documents showing tax withheld, such as your W-2’s or any 1099’s. Use a mailing service that will track it, such as UPS or certified mail so you will know the IRS/state received the return.
Federal and state returns must be in separate envelopes and they are mailed to different addresses. Read the mailing instructions that print with your tax return carefully so you mail them to the right addresses.
To change to e-filing:
It’s said I cant sent files by E-file because some reason but I don’t get why? Because my friend can but I can’t. I look though every detail of my information and it’s all collected
We cannot see your information and do not know why you cannot e-file. If you are filing by mail, make sure you attach any W-2's or 1099's that show tax withheld. The IRS will not make a direct deposit to a foreign bank, so if you are getting a refund it has to be to a U.S. based bank account in order to get a direct deposit, or the IRS will only mail a check to the address you enter on your tax return.