If I have Canadian PR and am an immigrant, :
1) Do i need to show my WES report of my Bachelors to take admission in Canadian University for Masters admission?
2) If yes, WES is valid for 5 years. After 5 years do i need to do a WES again?
Cannot answer your specific WES question but maybe ask the Unversity you are thinking of applying to what their admission criteria is given they do vary. Admission criteria is often stated on a university website either generally or for a specific course.