I am new to Scrum.I have few doubts.
who will cancel the scrum and How to cancel a scrum?
Why do you want to cancel a Daily Scrum ?
Maybe you mean cancel a Sprint?
Only the Product Owner can cancel a Sprint. He will do so if the Sprint goal does not make sense any more.
All done PBIs are reviewed. All undone PBIs go back to the Product Backlog and the team continues with a new Planning for the next sprint.
I don't really understand the question? And also - if you have doubts, are you talking about not using scrum at all?