A Few Newbie Questions

Hi I’m looking to become a merchant mariner but I have a few questions. What does a union actually do if you join one do they help you find a job or how does that work? Is there any permanent positions with a company in entry-level jobs or is just doing contracts like a mercenary/hired gun and floating around? I live in Oregon where it seems there is little to no entry-level job openings do they come and go or do I just live in a “dead” state? If so what is it recommended that I should do? Sorry about all the questions and thank you so much in advance. :slight_smile: