@baggerlord,
first of all I would suggest thinking about your desired income structure.
Do you like to get paid on a fixed salary + bonus or are you comfortable with performance compensation only.
This is a prime decision you have to make first in case you want to jump into it.
If you like to have a salary, you basically have no other option than to apply for a job at top tier firms like Renaissance, Jane or similar. The entry criteria are pretty tough though, so keep that in mind. So your chances are pretty slim in this case.
In case you are comfortable with no salary but a split of your profits, the situation is different.
You can apply at real prop shops and if you accepted, expect that you wont be making a dime during the first 1 - 2 years. That's how long it is usually going to take the average person to pull out $$ from the market. After year 5 you are probably good enough to make serious cash...if you can stick around that long.
As already mentioned, you need to look for shops that are taking the risk for you. If someone asks you for a deposit or a training fee, run away!
With regards to your background, I'd say that your military background will help you in terms of staying disciplined and keep up a routine. But performance under heavy stress is not necessarily needed, to be honest. Trading is not and should not be stressfull, especially not if you are spending an entire day in front of the machine untill your ass gets numb.
If you have stress during trading, you either trade too much size or don't know what you are doing. The key to become profitable is tenacity,patience, building routines, journal every day and developing strategies from it again and again. It has nothing to do with hyperactivity like you see in the movies: Like answering 100 phone calls in two hours while punching in 500 orders into your machine.
It's more like sitting and watching for hours until you find your spot to execute and do so without hesitation and flaw.
Which again leads to the compensation topic i talked about in the first place. Are you ok with the fact, that you might sit for days or even weeks, make no money and staying calm? If you freak out and be like "I have to make $$ to pay rent" and fuck up because you punch in a hail mary trade, that can end your career.
Just my 2cts.