Almost all Universities in Canada give preference to students with 10+2+4 or 16 years of undergraduate education. That is, four years of education after High School/ Junior College.
If you do have a 10+2+3 or three year degree from an Indian, Australian, New Zealand University or such similar three year degree program, you will not be eligible for admission to most of the Master’s program in Canada. You will require a professional four year degree like Engineering or other such courses.
On completion of a 3 year degree program like B.A., B.Sc., B.Com from any of the Universities, the advisable plan of action to maximize eligibility is to do a two year post graduate degree before applying for the Universities in Canada.
The second plan of action would be to do a one year postgraduate diploma (PGDM) from a recognized University after 10+2+3 or your 3 year degree. The key point is to ensure that the PGDM program you do is a recognized University program.