Can I, though, leave you with a suggestion in case you are really interested in tax work? I would get a CPA (Even if it means getting a bit of college under your belt.) And then I'd focus on providing complex tax accounting services like corporate returns, partnerships, t...rusts, etc. You'd want to first work with someone else to learn the ropes.
If someone doesn't already meet the education requirements to sit for the CPA exam, I think shooting for an EA is a better idea. I think an EA is a good idea for someone who is undertaking just a side gig, even. To go for the CPA from scratch, you're looking at a multi-year education commitment to get the correct credit hours in most states, plus an experience requirement. Study materials and exam fees can also be expensive if you don't have a firm covering it.
Doing the EA on the other hand has no pre-education requirements, cheaper exam fees, cheaper study materials, no extraneous non-tax sections, no experience requirement. Yes, the back end value is lower than a CPA, but so is the time commitment and monetary commitment. Combine the EA with QBO Pro Advisor training (which is free), and the person could throw bookkeeping into their bag of tricks for year-round work. QB makes payroll an easy service to offer, too.
Seems like it could be a pretty good side gig. You could learn as much as possible about the tax code, use it to help other people get the most out of their tax returns, and apply the knowledge to your own situation as well, and get paid for it! Low overhead aside from the initial $5000 bond.
For some people, it's low overhead. But would it be for you? The problem with being uncredentialed is that it's hard to attract clients. You kind of need a store front. A lot of people in your shoes find empty office space in dodgy strip malls and convince the landlord to rent it to them for 4 months. Then they survive off walk ins and do the tax returns while the person waits.
But if you're going to run that type of business, you're looking at getting super duper familiar with EITC due diligence requirement and probably offering bank products (tax refund loans, direct-to-Walmart-gift-card, etc).
Or maybe you're just thinking... "No, no, I just want to offer this service online for cheap and do it in the evenings." It's hard to predict. A savvy website and a cheap price might get you somewhere. Most professional tax software have a pay-per-return option where you pay some small base fee for the software and then $15 per return or something (my software, for example, on a PPR basis, costs $300, which includes the first 15 returns, then $20/return thereafter).
And sure, people do it as a side gig. Usually it's CPAs with full time jobs elsewhere who are doing it in the evenings and weekends with 20 or so clients. And it's money. But is it real money? I don't know. As an uncredentialed part-time preparer, you might be able to squeeze out $15-$20/hr after software and other costs, if you ignore any unbillable time (networking, talking to potential clients, website setup, software setup, buying supplies, education, research, etc).