The requirements to study in Canada at doctorate level vary to universities but you generally need the following:
    A master’s degree in a related field, with strong grades and proven research ability and potential.
   English proficiency tests like TOEFL, IELTS etc,
  A strong score in a graduate admissions test Graduate Record Examination (GRE). You can check the information all about of GRE with the given below link.

https://studyabroad.careers360.com/articles/what-gre

Good Luck!