See if we keep aside the branches then IIT Kharagpur is one of those institute which provides lots of opportunities even if you are not in good branch. Now coming to both branches then see in naval engineering placement has decreased but if you study hard then you can easily get placement or else many end up studying abroad. 

Fir agricultural engineering you get lots of opportunities you can start s startup. You can get a job in firm or consultant office. 

So it's completely upto you what you like. 

Thank you.