Maths Spl

Yes, you can apply for M.Sc in geology in NITs.

You can do M.Sc. Mathematics after completing BE.

If you score 27 in JEE Mains in math, you may get admission in B.Tech.
If you have 27 marks in 12th board exam, then you have to pass this first and then you can go.
All the best.

Please refer to the link provided below where you can download college brochure which contains details regarding admission protocols followed to secure a seat in this course.
https://www.shiksha.com/science/course/m-sc-mathematics-veer-narmad-south-gujarat-university-surat-171729
Alternatively, visit college web site for details regarding admissions for this course.
(Website:- http://www.vnsgu.ac.in)
Regards.

Once you have cleared all your exams of class 12 you can pursue various UG courses of your choice, however you may be required to appear for an entrance exam to secure a seat in the course and college of your choice. Regards.

To receive admission in M.Sc Physics course, candidates must have had graduation degree in specified specialisation (physics). For the courses having entrance examination and interview, the admission to the course will be through an entrance test, which results in the shortlisting of the candidates for the interview. 50% seats shall be filled by direct admission of the students of the University of Delhi only, on the basis of merit. This mode is not available to students from other universities. Remaining 50% of the seats shall be filled through entrance examination and Interview/Group Discussion if any.

You first need to decide what are your career aspirations and interest areas. based on it, decide which course to pursue. If you pursue a course which falls into your interest area, you will reap good benefits.

Please check for admission details regarding this course at college website. (Website:- http://www.davuniversity.org)
Alternatively, download college brochure from the link mentioned below, for details regarding admissions and eligibility to this course.
https://www.shiksha.com/science/course/b-sc-hons-in-mathematics-dav-university-jalandhar-266569