There are a few options here, including 3D-printing-as-a-service. Depending where you are, there may be a makerspace you can visit - even my local library has a small 3D printer available for use
I do wonder about longer prints and how that might go, but that's a problem for another day.
Re: 3d printing as a service, when I googled it here in Australia it was plentiful, expensive, and mostly focused on higher quality materials - for prototyping serious gadgets, it seemed. There were generic websites that seemed to be based overseas, but the options (and therefore my guess at quality) were behind a wall of lingo and technologies. I would have needed several hours I think to google, ask LLMs, etc, before understanding which to choose. And then? They were still not particularly cheap -- I expected to spend less on the case than the screen.
there's also services like Shapeways which can print in basic or exotic materials and ship them
Plus, picking up a print gives me a reason to go to the library, which I love.
I generally print and send small things for free, for anyone who asks nicely in certain forums and discord servers so long as they're local (country) or want to pay the shipping.
3D printing is a hobby for me, I use it for functional prints mostly, and I love for people to experience what I did the first time I got my hands on something 3D printed.
I used 3D print services at first, but I found the quality from some of them wasn't up to my standards; they're optimising for speed and profit, fair enough.
If you have little money and more time and patience, Creality Enders are a good basic introduction to all the nuances, pains and heartaches of 3d printing but will give you a better idea of fundamentals. ($100-300) Expect to lay out another $100 for filament, upgraded bed and other small parts like bed springs.
Don't buy a used machine as a starter because you'll just be taking on someone else's headache, but once experienced you can find some craigslist and offerup deals for spare parts or a small print farm, occasional like new "used twice" $50 printers.
If I was starting over, I would get a BambuLab A1 https://bambulab.com/en-gb/a1
If you want to spend less, you can get an Ender 3 or one of its many clones https://www.creality.com/products/ender-3-3d-printer
I advise against self-assembly. Especially for your first one, let the factory assemble it. Doing it yourself significantly increases the likelihood of alignment/calibration problems.
These will be frustrating and hard to chase down, especially if you don’t have a mechanical background. You can make a whole hobby out of building, modifying and upgrading 3d printers… but that’s a very different thing from using a 3d printer as a tool for other projects.
I avoided buying a printer for years and years because I wanted to print things, not spend my time tuning and tweaking the printer. finally broke down last year and bought a Bambu P1S with the AMS for multi-material printing and it's been a revelation.
It's truly set and forget. Keep the filament dry, keep up with routine maintenance and you'll never have to worry about a failed print.
I'd still personally recommend something like the (new) Ender 3, or similar, not because it's a great printer, but because the community around it is huge; you'll be able to get lots of help, and there are plenty of mods. Have a poke around Reddit etc and see what the most popular model is these days.
After a couple of years I heavily modified the E3v2, to the point nothing but the frame remains, and then I build a Voron v2.4 (350mm).
Once I had a printer, I started learning to design/model things, learn how modeling for 3D printing is different to other forms of manufacturing, and then just make things you want/need.
3D printing is still a hobby for me, that's the way I'd like it to stay so I've got no advice on making things for sale etc.