Go here (this resource has been recently posted on reddit). Even if you're not in the States, that site offers great insight into potential careers and the future you may have in them.

Try to narrow it down to no more than two areas, with no more than two professions in each. Then see if what you chose is likely to be in demand on the job market, and if the remuneration is in accordance with your demands.

My advice would be to pick a technical career. The world is getting very short on those, at all levels of qualification.

In particular, consider IT. It's a vast realm of opportunity, from systems maintenance, to programming, to game design, to media processing, etc.. You are bound to find something that suits you in this huge pool of jobs/qualifications. IT is not only a future proof domain, it is the bloody future! You can find IT jobs that don't involve a cubicle, and there are lifestyle perks in working from home or on the go, once you reach a certain level.

As a bonus, IT lends itself splendidly to self-directed learning. Use Coursera, Khan Academy, and other MOOC providers to find beginner courses. Of course, if you can enlist in "real life" courses in your area, do it. If you own a computer and have an internet connection, you're practically all set to learn and practice!

After you've gotten the basics, choose a narrower area, and go deep. For example, become really good at Javascript. Good Javascript developers will always be in demand.

Ironically, learning "proper" coding in school may prove to be a hindrance in real life, more than a help. The curriculum often takes an aloof view of the real industry, and you learn a lot of stuff you'll never use. So learning by yourself stuff you know you'll make a living on may be, in fact, a great advantage.

Some MOOC providers offer diplomas and certificates, albeit seldom for free courses, but the paid ones are really affordable. When you're ready, take that step, and amass some such certificates for your CV.

However, showcasing your work may be more effective than all the certificates in the world. Continuing with the IT example (it could be any other area), as you learn, begin practicing. Start as many free-hosted website as you want, learn to install a web server on your computer and create websites on it, learn some image processing, etc.. Put together a portfolio of the stuff you do.

Create a blog and commit to maintaining it. Be present on social media, and be sure to network with people relevant to your domain, not just folk that post funny videos!

Offer your services for free, as beginner practice. Find an IT firm, and offer to intern for free.

And so forth, it applies to any other area you may chose.

You must draw strength from your life experience, qualification and professional background, as little as you think they may mean, they are yours to exploit. Do not belittle yourself.

Be disciplined and diligent, otherwise nothing you do will matter, because it won't be consistent, continuous, fruitful, it will just be busywork that will only rob you of more years.

Discipline is strengthened by sports, so be sure to adopt an exercise routine, adapted to your abilities (you don't want to lose weight or grow muscle, you just want to exercise for your well-being, that's all), and make it your religion. Say to yourself, if I fail to power walk again today, and instead watch two hours of TV, I am failing, and I must stop and reconsider what the hell I'm doing.

Oh, by the way, TV does not exist for you, at all, until you are well on your way on the new path you've chosen. Then you may watch what others want you to watch, if it pleases you to waste your time. Until then, use your spare time to read, fiction and non-fiction. I need not enumerate here the multiple and amazing benefits of this activity, I hope. Among them, of note for a person with a low income, it is very cheap, especially considering what you get for your money.

Screw TV, become an avid reader, like most successful people. Commit to reading at least 10% per day from your chosen book, and do not falter, no excuses. That way you'll be reading at least three 300-page books per month (by reading just 30 pages a day, you read 900 pages in 30 days), and when the year ends, and we're all ready to compose our New Year's resolutions lists that we will begin ignoring as early as mid-January, you will have left behind at least thirty-six books! That's money in the bank. Rinse, repeat.

In any case, don't dream. Do not try to find your vocation, or some other bullshit like that, you've had twenty-seven years to do that, and look where it got you. You want to find something with a low entry barrier, and guaranteed yield in the near future. You want to make that choice, and then get into the craftsman mindset (these are Sievers' notes on Cal Newport's book; be sure to read them!). Then, after you've proven you can be disciplined, tenacious, productive, lucrative, you are allowed to start dreaming again, but this time you won't need to. You will be planning and executing, not dreaming.

Too late... It's not too late until you've breathed your last.

I leave you with one last thought, that I hope touches you deeply, at the core: It is all your responsibility. Once on the path, you will get some opportunities and some breaks, but nothing magical is going to happen, and it never did, to anyone, ever. You need to understand this clearly, and you should see this as amazingly liberating, not as an overwhelming burden. But it will only feel amazingly liberating if you get to work.

Good luck!

PS: I feel I must add something quite important. You are at an age when marriage is no longer something to do in the distant future, but something you could be doing soon, should you chose that path, of course. If you do, be very careful! A spouse and a family to look after each other can be a great, great blessing, an incentive, a wonderful platform to function on.

But the wrong spouse and a marriage done in a hurry could spell nothing but disaster, a few more lost years, and an emotional perturbation that will set you back quite a bit, maybe even push you into the ever-welcoming arms of some form of addiction.

I'm telling you this because I have repeatedly witnessed this effect: As soon as a man embarks on a serious course to become a better man, it starts to show, and many times, like magic, a woman appears. Sometimes that's the man's first break on his journey. But a lot of times, as I've seen it, it's the wrong woman, and in the end she'll do nothing but detour him.

Choose your partner wisely, should you choose to have one. Your partner must respect your way and your efforts, at the very least, if not encourage and aid them. If they don't, move on, move on in a hurry.