Hello @RuthVella 

When you create a quiz, under the edit side there is box for these options. By default the option "Let Students See Their Quiz Responses (Incorrect Questions Will Be Marked in Student Feedback)" will show students their responses. Answers that were marked correct will be displayed as such. Answers that were wrong will tell them it was wrong but not explicitly tell them which is correct. If you want that enabled, you should also enable "Let Students See The Correct Answers"

However, if you want the students to see nothing after they submit their tests - disable both of these options. You can always come back after you are finished grading and let the students see their answers. Your best bet is to keep them disabled as student A could take a screenshot of their correct/wrong answers and share it with student B, etc. 

Here is the Canvas guide:

https://community.canvaslms.com/t5/Instructor-Guide/What-options-can-I-set-in-a-quiz/ta-p/683