When setting up an Apple Id and password for an iphone 5s, do you need to plug in the USB to the computer and the phone?

Do you hook up USB plug to phone and computer to sync it, or do you just create the Apple ID and password?

No. Ever since iOS 5 (2011) it isn't required to connect your iPhone to a computer since you can setup the phone directly on the phone. Pre-iOS 5, it was required to connect the device to iTunes to set it up, which was very inconvenient.

Shouldn't matter in that case.