Answer:
What goes up but never comes down?
I'm a small ring shaped fried cake, often with bavarian cream or fruit filling, and sometimes covered in icing and sprinkles.
It goes up and down the stairs without moving.
What kind of room doesn't have physical walls?
What is found over your head but under your hat?
It flows out of the soil, It burns you if it boils, And holds us in its coils, More valuable than gold, As black as it is old.