Hii,

No you cannot join the Merchant Navy as the elegibility criteria include..

To join merchant navy , you must have studied maths , physics and chemistry at +2 level.

Candidates who have studied these subjects usually pursue marine engineering or nautical science to join merchant navy

Merchant Navy has various departments and all the departments have various domains and every department has its different eligibility criteria to get into,

And every department needs Mathematics as the compulsory subject in class 12th.

Hope this will help you,

All the very best!!