The best way to get to multiple six figures without going into debt/years of school is Sales.
I'm not talking about used car salesmen here, but sales functions within the commercial arms of Fortune 500 companies.
My career has been in this area and has covered medical device, specialty chemicals, and biotechnology.
Pros: High degree of autonomy, clear understanding of value creation for self/firm, new experiences constantly, significant visibility in company
Cons: Absolute accountability in a way most roles can't imagine, high pressure, travel can be 80% at times, customers can be pricks
Benefits: Two types of comp packages are typical; 1.)low base (70-90k) with uncapped commission structure (think 20% of gross sales over target) with total comp realistically hitting 300k+ in good years. 2.) high base (120-150k) with capped bonus/commission structure with total comp hitting 200k+. Type one is typically for business that aren't market leaders and require more of a hunter mentality. Other benefits- all these roles usually come with a company car/stipend, home office allowance (internet, phone, etc.), and standard mega corp benefits/retirement packages.
Often these roles have titles like: Account Manager, Business Development Manager, Commercial Director.....they're all ways of avoiding saying salesman....at the end of the day nearly every product you see/touch has to be sold by someone and that person is typically getting a cut.