as far as i know, civics test is usually the first thing after taking oath and checking your ID. however, it does not preclude the IO from asking questions first if he has something on his/her mind. this might be the usual practice, but not the rule.
they ask up to 10 questions, when you get 6 (or 7) right, they stop. the questioning is oral .. they read a question, you answer. you can answer any one of the answers listed in the guide. they will not give you multiple answers and ask you to choose, you need to remember. besides the civics test, they will give you one english statement to write, and one english statement to read.
[EDIT/ADD] sorry should have clarified ... it is part of the interview process. thanks mogambo, my response was unclear.