As you want to get the details of eligibility and process to join Merchant Navy so here is the information of the same for you:

The eligibility criteria for the different types of entry in Indian Navy as a sailor is given below:

(10+2) Executive, Engineering Electrical & Naval Architecture
Candidates must have passed 10+2 examination with Physics & Maths
Candidates must have minimum and maximum age of 16.5 and 19 years

ARTIFICER APPRENTICE:
Candidates must have passed 0+2 examination and having subjects Physics and maths at 10+2 are eligible to apply for this entry scheme.
he candidate applying for the above entry scheme should have minimum age 17 years and maximum age of 20 years at the time of training.

SENIOR SECONDARY RECRUIT:
Candidates must have passed 10+2 examination and having physics and maths as a compulsory subjects.
Candidates applying for the above entry scheme should have minimum age of 17years and maximum age of 21 years.