Hello @cmccann1
Thanks for posting this in the Community!
I saw your question here and wanted to add a bit of my own experience with this.
As mentioned previously, there is not a intended way to do this. Mostly because Canvas quizzes will ask you how many points you want to associate with each question. However I once had a teacher get creative with this and thought I would share it.
Essentially they would use the Text: No question(classic quizzes) as the very first question on the quiz. Within the Text: No Question, They would list the questions that students can then respond to within that field. They would make sure that the option for Show One Question At a Time was not selected within the quiz settings. (This will allow them to go back and view the Text: No Question at the top of the quiz taking page) From there, they would place essay questions within the quiz. Students would then be able to respond to a question of their choosing within each essay question that is placed on the quiz. One thing they did was that they would specifically ask the student to clarify which question they were responding too within each essay question so that it was easier to grade at the end.
If you are using New Quizzes, there is a stimulus feature you can use to attach the essay questions. Again, you would attach 5 essay questions to the stimulus and students would need to explain which question they are responding too at the time.
Not the cleanest way to accomplish this..but it is a work around I have seen used before! If you have access to a sandbox, you could try it out and see if it work for you in student view.
Hopefully this helps!
-Colton