Check the country list at the bottom of the article you were reading () to make sure two-step verification is available in your country. If you don't see a link to reset your security questions it's probably because you never added a rescue email address to your ID. If that's the case, you'll have to contact Apple for assistance by going to https://expresslane.apple.com, then click More Products and Services>Apple ID>Other Apple ID Topics>Lost or forgotten Apple ID password. If you can't do this, contact iTunes store support for assistance by filling out this form: https://www.apple.com/emea/support/itunes/contact.html.