iTunes cards can only be used for stores in the country where you purchase them. He would have to be using the US (or wherever you are) store and that is not allowed from Syria:
http://www.apple.com/legal/internet-services/itunes/us/terms.html#SERVICE - Jan 2018 "Our Services are available for your use in your country of residence (“Home Country”)."
Also, I don't know what he means by gain access to the Internet. iTunes cards won't do that, they only let you buy things on the iTunes store which isn't Internet service. You have to already have Internet service to do anything on the store.
Telling people they need an iTunes card for paying for something is a practice used by scammers, by the way.