I would like to know if there is a way that when they fail a question I will not tell them if they have failed or not, until the end of the test
Hi, that isn't currently a feature in the quiz and flashcard resource types. However, we'll look into adding it in a future version of the platform.
In the meantime there is a feature to disable the student's ability to 'reveal the correct answer'. To disable that functionality open the quizzes' dashbaord and click 'Quiz Settings' then under 'Reveal Answers Option' select hide. You could also make a 'survey' which doesn't have correct/incorrect answers if you were just interested in collecting responses from students.
The Topgrade Team