Getting a business license as a solo practitioner costs $40 in my state.
If you need to hire your first employee, your state likely has some simple instructions on how to do so. And if you can hire an employee, you can also pay for an accountant to help you with payroll, file taxes, etc.
This is how, like, 90% of small businesses in America get started. Your average restaurant owner never went to business school. If you are not incorporated, business finances are pretty understandable.
If you really want to go big to start out, you can look at a service like Stripe Atlas that should walk you through incorporation.
I'm not saying business school is a waste of time. But if you are motivated and already know what you want to do, you can learn all the same things faster and cheaper by just getting started.
The IRS has a lot of online information on starting a business, but it's buried in multiple documents. The best overall guide I know of is Publication 334: https://www.irs.gov/publications/p334
I think it's a matter of personality. Some people want everything analyzed before they start, but I'm not much of a planner. I just jump in and see how the water feels.
aside from just plunging myself into the depths, shouldn't i be somewhat prepared and smart about what it's like to think about company finances? or are people literally just doing and failing and learning on the job? seems very costly?