There will be many average to best tutors and classes available that I can enlist down and I surely will. But more than them, it depends on the student, how dedicated and devoted he is to achieve his dreams and goal. So you need to have a very proper schedule being followed every single day if you want to crack the exam. So some of the well known tutors are -

1. Aritra Roy (Msc Mathematics) and the classes name is TeacherOn.
2. Unacademy has also proved to be good as per the toppers reviews.
3. Edurev
4. Eduncle
5. VPM Classes

Best wishes. Thank you.