Degree

To seek admission into IIM-B you need to score at least 50% marks at graduation exam and must get 98+ percentile score at CAT. You also need to perform well at the personal Interview (PI). However, the percentile required will depend a lot on the score of other students as well.

I would request you to contact the college authorities to know about the procedure.

For admission in B.Com at S. Khanna Girls' Degree College, Allahabad, you need to go through counselling based on the Post Graduate Admission Test (PGAT) conducted by University of Allahabad.

After Diploma in agricultural engineering, you cannot get B.Com most of the universities require Management or Commerce or Economics in Diploma.

Certificate in Statistical Methods and Applications
Diploma Courses in Statistics
Bachelor of Arts B.A. In Statistics
Bachelor in Statistics
Bachelor of Science (Hons) in Statistics
Exams for statistics:-
Aligarh Muslim University: Department of Statistics and Operations Research Entrance Exam
Indian Statistical Institute Entrance Exam.

Yes, you can. Since, you are pursuing B.Sc in stats and MBA in data analytics, it would be an advantage for you.

Yes, you can pursue MBA. However, since you a BE & LLB, I would suggest you- first, you need to decide on what are your career aspirations and long term goals & based on it, take a call on pursuing further education.

Of course, you can pursue a B.Com with private degree. You just fill up the form of Rajasthan University for B.Com private and then get admission.

If you have completed Diploma in agricultural engineering, then yes, you can apply for the degree.
All the best.