It depends on what you want. The simplest way is to edit the built-in Try again or Incorrect layers for each question. It's also probably the most effective way. as feed is more valuable the closer it is to the learner's choice.
If you want to wait until the end, then yes, you will need to keep track of the specific questions that are missed. You may be able to find a way to make the built-in review work, otherwise, you will need to use a bunch of variables. Each question will need a unique variable, unless things are arranged so you can say, "If you missed question 6, 7, 8, 9, or 10, review this material".
