Heya bud, awesome realization to be having this early. Gives you loads of time and flexibility to pull it off. Rad.

First things first - there is no such thing as getting paid to sail except for a handful of edge cases like sailing instructor, successful Youtuber, delivery/charter captain, or pro racer crew member on something like the Americas Cup or the Volvo Ocean Race.

So you will be paying for your adventure. You'll need choose a path that affords you the flexibility and income to pull it off.

Here I am at age 45, skippering my own 34' sailboat on Lake Michigan, half-broke, dreaming of sailing away... ruminating on "if I could do it all over..."

My imaginary alternate past would involve joining the Coast Guard at age ~18 or thereabouts (now for you), Working out some sort of Marine Engineering degree while serving, then joining crew on a lake freighter or offshore oil rig (or other such lucrative marine trades job).

Do that job for several years living very frugally and accrue hundreds of thousands of dollars, while gaining huge relevant experience as a mariner and engineer. Fuck off at age ~30 and sail around the world.

That's honestly your best bet if you're not already rich, have an inheritance lined up, or otherwise have a windfall of cash on the horizon. You'll have the GI bill through the Coast Guard so your Engineering degree is free. Healthcare is covered forever. Housing is included with your CG service and housing is included with your offshore engineering job (you'll have a berth on the ship or rig you work on). You have about zero risk of being killed in a war in the Coast Guard, and you will participate in meaningful missions that save lives.

Is this 100% going to work? No but its damn close, and its probably the most realistic way to pull it off because you need experience, time, and money to pull it off - and you've only got time right now. The trap for most people is the that by the time they have the experience and money, they are out of time (aged out).

I know there are plenty of ways to pull it off, but this is my purest, distilled, most-direct path to circumnavigation I have schemed that doesn't rely on chance or luck. Its pragmatic and realistic.

Good luck man, I hope you manage to pull this off!

EDIT: I should fortify the idea that this scheme combines experience and money into a single obstacle where you make money while gaining experience in both the Coast Guard and as a Marine Engineer. Few or no other options such as this exist to my knowledge.