It is not essential. There are many ways to achieve a quiz type example but some are easy some are hard. The more you want in the same scene the more it will become complicated.
Have a look here for options on how to keep score. There should be some examples here.
think of perhaps
localStorage to store the score.
I'm afraid I don't have much time to work on examples as you can appreciate but there are probably a few ideas here in the forums you can pick up on.
So in summary I suggest working on something and if you really stuck on something come back to the forums with what you've done and someone I'm sure will be able to help.