thanks for your valuable replies sir. I checked about this information in cic website and they wrote like this in GUIDE 5269
Do I need a Temporary Resident Visa (TRV)?
Citizens of certain countries may require a TRV in order to travel to Canada.
A TRV is an official document issued by an officer that is placed in your passport to show that you have met the requirements for admission to Canada as a temporary resident.
If you need a TRV, you do not have to complete a separate application or pay additional fees. It will be issued by the officer at the same time as the documents you need for your entry to Canada as a student;
Find out if you need a TRV or check Appendix A – Temporary Resident Visa Exemptions for more information on persons who are exempt from obtaining a TRV to come to Canada.
As they said that there is no need to fill another separate application for TRV( IMM5257B). I am thinking to leave it .
Please advice me if I am wrong.