I hope by now you have found answers to your questions. But to make sure the loop is closed here:
Question banks in New Quizzes are known as item banks. Instructions about adding all questions from an item bank are shown here: https://community.canvaslms.com/docs/DOC-26425-how-do-i-add-all-items-or-a-random-set-from-an-item-b...
You can duplicate a new quiz as shown in this lesson: How do I duplicate a New Quizzes assessment?