If we forgot Security Questions How can we recover ?

Go to https://getsupport.apple.com . Click 'See all products and services', then 'More', then 'Apple ID', then 'Other Apple ID Topics' then 'Forgotten Apple ID security questions'. If you have any problems with that try this form: https://www.apple.com/emea/support/itunes/contact.html

If you forgot the answers to your Apple ID security questions - Apple Support

https://support.apple.com/en-us/HT201485