When eligible to take a quiz you will see all the questions within the quiz once you've opened it.
If a strict order is enforced, all but the first question will be faded, if not you can start with any question you like. Should the quiz have a time restriction, a timer will appear on top of every question:
If a question(1) contains a slide it will be visible on the right side(2) see how to navigate slides here.
A slide can have more than one question, once you've selected your answers (3) and pressed next(4) you will be automatically moved to the next available question. Once you have answered all the questions in a slide you can press "Mark&Next"(5), if you would like to be reminded at the end of the quiz to come back to the question or "Save&Next"(6), to continue to the next part of the quiz.
Once you finish the quiz you will be able to review it:
If you missed an answer the question will be marked with an hourglass icon(1), if you chose "Mark&Next" a yellow flag(2) will make the question, the two green checkmarks(3) mean that you answered all questions available.
Once you've revised your answers you can submit your quiz.
Depending on the quiz type you may be able to see your results right away, or even restart the quiz.