I would appreciate if anyone can explain how to provide feedback and status(pass/fail) AFTER the user answers all the questions.
For exam : Student answers all questions in test mode, then the student is provided with pass/fail status with feedback on his performance by question.

If you aren't using an LMS to manage the module then you need to use the variables which the results are stored in.
If you add the RESULTS BY SELECTION from SIMULATIONS in the Object Library you can see what is happening and what you can use.
For example if the user achieves your pass score have a congratulations message or even a crtificate appear that the user can print.
Feedback is more difficult as you would need to do a lot of parsing to give the correct responses but could be done using the values in variables to act as triggers.
Sit down make a flow chart of what you want to do then build your actions and statements around it.
Rgds
Nick