Advice about the industry and getting started

Hi all.
I posted for some information about a month ago but need to elaborate a bit more on my situation.
I am a New Zealander and am getting married to a girl here in Boston. She’s in the medical profession and has a good job here.(I understand that Boston might/would be a home base for me and I would be travelling to other locations for work eg, The Gulf, West Coast etc.)
I am 38 years old and have worked as a rancher for a good part of my life. I have also worked in several kitchens and as a mate on a small charter fishing boat for 5 seasons out of Nantucket Island while spending summers here in the US.I am hoping to apply myself and get involved in an industry and make a career out of it. The merchant marine industry has been suggested to me as a potential option that could be cohesive to my personality, interests and achievable to get into at an older age and progress within.
I am not legal to work at present until my marriage paperwork has been processed/finalized. Any tips on how to spend my time productively to help getting started once I am legally allowed to work/obtain twic etc?
Also what is the job market like? How tough is it getting started/finding that first job? Any advice or warnings for me? Any info at all that you think might be good for me to know or helpful?
Thanks guys.

Once you’re legally able to, and get a mmc/twic, you’ll be able to find work, assuming you’ll be willing to travel. You can probably find work for shitty money on passenger vessels out of boston with just a green card or citizenship and no credentials at all. Maybe a lobster boat for cash without at immigration paperwork. Work is available in the industry and will continue to be so. There are plenty of people from other countries who have moved here and with proper paperwork have been able to get into the business. Bottom line-you’ll be working entry level for a while, and until you’re a citizen you won’t be able to be an officer (deck/engine). You can find work in New England/NY although probably not close to ideal conditions until you get experience/paperwork.