MPC student can pursue Defence Services through NDA which requires Mathematics in Class 12, so you have an advantage of choosing Physics, Chemistry and Maths subjects.

Besides becoming an Engineering aspirant, you can wish to choose Biotechnology field, or go for higher degree in Mathematics and Statistics.

If you are fond of chemical reactions, you will love to have higher degree in some field of Chemistry and research and publish your own Chemistry papers.

You can also go for B.Sc programe in particular field as per your interest, It all depends on your Career goal & interest.

Good Luck!