u/Alarming-Mix3809 is quite correct - you’re putting the cart before the horse. Dig in and really do some learning before you move forward.
Start with figuring out what you want to sell, interviewing suppliers and getting reference accounts who are willing to talk with you.
Style tip: wear a top hat with your monocle. :)
Yes, your experience is quite common. You can tell people, “This is harder than it looks, riskier than it looks and less profitable than it looks” until you’re blue in the face, but it won’t work. I just say, “Get a job in corporate; it’s less work and less stress.”