forgotten Apple ID security questions and have no rescue email adress

Either use the link on the page that you posted from (under the 'If you can't reset your security questions' heading) to contact Support to get them reset, or select your country on this page : Contact Apple for help with Apple ID account security

If your country isn't on that page then try this form to contact Support : https://www.apple.com/emea/support/itunes/contact.html

When they've been reset you can then add a rescue email address for potential future use : Manage your Apple ID primary, rescue, alternate, and notification email addresses

Or if it's available in your country you could change to 2-step verification : Frequently asked questions about two-step verification for Apple ID