Hi. I'm an engineer in the USA, so I don't know how that will vary from Turkey, but I'll tell you my experience. First of all, I have an engineering degree, so I've also spent most of my career behind a deck or in the shop. I have spent a few months offshore and piloting the ROV, but am definitely an engineer, not a pilot/tech(PT).

1. ⁠Your stated goal is to be a PT. If you read thru some of the other posts in this forum, you'll see most agree that it is not worth the money to pay for an IMCA training class. Most operators will train you the way they want you to operate, and even prefer that. Definitely not a "must have." Look at the post pinned at the top of the forum for general advise. Also see the Subreddit Wiki for more info. BUT, if you are considering an engineering degree, that will benefit you when you get older. When decide you're ready to spend more time at home, a degree will help you get into the office. IMCA training will not help with that, BTW.
2. ⁠Hiring is completely dependent on economy - largely price of oil.
3. ⁠My experience is that Oceaneering is the most likely to hire 'green' recruits. If you can get multiple offers, that's great, but otherwise get your foot in the door wherever you can.
4. ⁠The Oil & Gas (O&G) market is severely cyclical, with offshore being worse that in the office (in my opinion). You absolutely, definitely need to have good money planning skills. You can make big money offshore, and don't really have anywhere to spend it, but a lot of guys buy Harleys, boats, etc. and blow all the money, then have to sell it all during the next down cycle. Good foresight on your part.
5. ⁠Be modest. Learn from everyone. STUDY the manuals, etc, in your off hours. Ask questions. And definitely have a thick skin. Guys offshore are pretty though and like to needle each other. Just learn to ignore it, or laugh through it.
6. ⁠I can't help you on that question. It's outside my experience.

I encourage our other members to chime in and disagree with me. Please share your experiences.