Is your question about the square enix name and password and the one time password? Or just the one time password? If the latter, you don't need to worry about it. That's only if you have a digital password token signed up and linked to your account. If the former, you would need to create an account here: https://secure.square-enix.com/account/app/svc/Login?cont=account
After creating an account, you would then link the Square Enix account and your PSN account. On the other hand, if you already have a Square Enix account and password, just login with that and ignore the one time password. I hope this helps. If not, or if you have any more questions, feel free to ask.
Primary World: Hyperion
Free Company: Jormungandr
Main Character: Fialas Dawnren: Level 60 BRD/AST/MNK/DoL, Level 16-50 On Everything Else