Are you sure It's still a thing? I remember reading an article in Coindesk about registrations being opened again in the exchange but only for Koreans and according to a review from worldcryptoindex:
Level 1
Level 1 requires only email and SMS verification. With a level 1 account, you can deposit an unlimited amount of virtual currency into your account, but no KRW. You can not buy or sell any currency as a level 1 user.
Level 2
Level 2 requires further identification confirmation which includes everything from level 1, in addition to a cell phone, submission of the user’s passport, and I-PIN ID confirmation.
I-PIN ID confirmation is something you could only get from Korea I believe so even with a passport, you can't do much. You probably have to contact the support for a better clarification.