2) What instrument he is going to play?
He is going to play the pipe
3) What they are going to do with the present?
They are going to gift the present.
4) What are you going to have?
i'm going to have a cake.
5) How they are going to get home?
They are going to get home by a bus.
6) Who he is going to ring?
He is going to ring his friend.