Thanks for A2A

Well, firstly congratulations for your decent performance in JEE advanced.

Regaridng marine engineering, you'll get to learn more the engineering of ships, their design, instruments engineer use to navigate.

Regarding placement senario

It has little less jobs as comparison to the core jobs, but if you worked had at IIT M

Then you have a very good chance of getting into the prestigious Indian Army at the rank of naval commnader whose salary with all the allownaces hikes to over 20L. But leave this salray, you'll be among the elite sevices and recieving loads of social prestige and job satisfaction.

I would end by saying, every branch is excellent, provided how good you can make out from it!

Thank You