Sorry to say, but you're wasted your money. If the phone was in DFU mode it most definitely was NOT ready for a new user and unless you know the actual Apple ID and Password which was used to set up that phone to begin with, you cannot get past that. And even if you did, that phone is not LTE capable, and most of the world has turned off the 3g towers. The phone you bought is virtually worthless and there really is no one who can help you. Apple won't offer any help with it at all. That phone was released in 2008 and is now beyond an obsolete no longer supported phone.
If there is any way to return the phone and get your money back, do that. If you can't, just recycle the phone responsibly as there is no way you can restore or use it.