Look, Nou's right. There are guys out there who pour hundreds upon hundreds of hours into developing content for ArmA that don't receive any kind of support or if they do, it's very little (read: fucking tiny) in comparison to the work they put in. These are also real people, with real responsibilities, and real life jobs they have to work in addition to anything they contribute to Arma.
BUT I don't wanna be Debbie Downer, and just leave you with a negative vibe.
Want a chance at success?
You need to do some work. You need to at least get out and shovel snow or what the hell ever it is kids do for money these days. Set up a server, grab a clan site or your own domain, and build it up.
Doing these things shows that you have initiative. If you have initiative, a willingness to learn, and a bit of creativity, you can do some fun things with your server that will bring in players. Some of whom will donate money to help with operation costs IF YOU PROVIDE A FUN, ENTERTAINING SERVER THAT THEY WANT TO KEEP COMING BACK TO.
You're not going to get rich running an A3 server, and you'll probably still end up going into your own pockets to keep things rolling, but this is good life experience. Especially at your age.
Here's a real life experience of mine I'll share to give you some perspective: I worked 10 yrs in the oil/natural gas industry with a group of contractors. The pay was nowhere near as good as what you'd think because we're in the southern U.S. and non-union. Extreme hours, shitty conditions, and only the most basic safety precautions (other than those enforced by the major natural gas companies... those guys are legit regardless of what you may hear). I hated it. We had good times. A bunch of blue collar guys cutting up and all that, but I wasn't making enough money. I knew if I didn't get out that I would be doing that shit til I was 70 or dead, so I started scraping and saving every dime I could get. I started doing side jobs on the weekends. I was big into film as a kid and (big whoop) as a community college student, so I started studying cinematography and video editing on my own time with every free resource I could get my hands on. Finally, I took the money I saved, bought a camera, some equipment, a computer, and started a video production company on the side. I finally left my job and started working on videos and photography full-time...
AND IT FUCKING FAILED.
....but I learned a lot. Now, I'm building it back up to go again, and thanks to hindsight, I think I've got it in the bag this time. Maybe not. Here's the thing though: Kids your age are being brought up in a time where everyone wants to be "funded". Everyone's got a great plan, but they don't want the risk or worse, they're totally unwilling to put the work in.
I'm not sure where you're from, or what your plans are, but if you want to succeed at anything in life, remember: You're going to have to work, and you're more than likely going to have to do it alone. Sometimes you get lucky, sometimes you crash and burn, but it all benefits you whether you realize it at the time or not.
Best of luck. Hope this doesn't deter you, but rather pushes you to strive onward. I'll be glad to help with any questions concerning anything you might run across moving forward as best I can, and I'm sure the rest of these guys will do the same. You just need to get the ball rolling on your end.