How do I get a social security # when I don't have an mailing address? I'm living in a hotel and may change.

I%26#039;m a J1 visa student in the US for an internship. I%26#039;m temporarily living in motels/hostels until I find a permanent place to stay, but need a social security number ASAP for work.|||purchase a PO Box|||Rent a Po box at a mail outlet.I believe to get a post office box you have to have a home mailing address