This is actually a very long long process. It is not like a 3 year course where you finish your graduation and starting a corporate life.

Its long and continuous process of training, courses, exams and promotion and takes many years.

Complete your 12th in Science stream with 65% agg. and then the choics opens up:

Diploma in Navigation Science (DNS)

B.Sc in Navigation Science.

For any of those two you have to give IMU-CET and you must score very good marks to get Anglo Eastern Maritime University.

All the best!!