Answer:
They keep secrets locked away. And you pass through them each day. For each one there is a key, They respond to sesame.
What has keys but no locks, Space but no room, You can enter but you can’t exit.
Take one royal word in the plural and make it singular by adding one letter
I'm a small ring shaped fried cake, often with bavarian cream or fruit filling, and sometimes covered in icing and sprinkles.
Take it and you will lose or gain more than all the others.
What has to be broken before you can use it ?
Easy
Animal
Difficult
Food
Funny
Kids
Logic
What am I?