You need enter shop at n11.com first in order to identify N11 Api account. Enter Api Accounts on My Information section that is located on the rightmost of the menu on shop management panel.
Click “Create New Account” button on Api Accounts section. Api key information that belongs to created API Account is displayed on the screen. AppSecret, in other word password information is sent to your e-mail address that is saved on N11. API password can be created whenever you want or API accounts can be deleted.