A2A.
Any reputed institute will try to cover the entire syllabus,rather Almost all institutes go in more detail than generally questions asked in exams ,as a part of their business strategy . If any aspirant go through previous ten years papers , then you will be in a position to highlight the important points in each chapter.
It’s least important,where from you get the study material . However your study material should consist the depth to cover at least more than 90 percent and it should be sufficient enough to be revised multiple times ,till exam period .