Hey!

For any exam cutoff is given in terms of scores and for any college/course under counselling cutoff is given terms of closing and opening ranks for the same college /course.

For ex. For jee mains cut off is 73, it means students who have scored more than 73 has qualified the exam. And in case of counseling, let's say that for CSE closing rank is 400 it means that students who have scored less than 400 rank are eligible to get cse in that college.

Also, you cannot buy any exam or course under any authority. But there are many colleges which offer some of its branches under management quota.

Hope it helped to clear your delimma

Thank you