It is hard, it is time consuming and it is risky. My father did start his own business after beeing fired, and since is barely scraching along ever since he started his business, although he is working all day. And that's still kind of a succes story, here comes some really depressing shit:
The brother of my roommate (we'll call him Matt) started an IT consulting company with a friend of his (we'll call him Steve). They founded a GbR, which is a German form of company where both fouders are liable for loans with their own private money.
At first, there were pretty succesfull, but then Matt's asshole chad friend Steve impragnated two woman. Since he had to pay child support for two children now he figured that a steady job would be better, and left the company. This is where the desaster begins: He took a job in a rival company and convinced the biggest client of the company he cofounded to switch to the company he now worked at. This was a devastating blow the company of Matt , and in the way Steve took his customer it was also illegal, but Matt couldn't really sue him because if Steve declared private bankruptcy the company would also become bankrupt. In the end, the company couln't handle the loss of its biggest client and went bankrupt anyway. And who has to shoulder the debt of the company now? Although Steve was clearly responsible for the bankruptcy, Matt has to pay the debt now, becuase Steves income can't be taken away from him because he has to pay for two children. Matt is now unemployed and has crushing debt.
So the moral of the story and the example of my father: Don't start a company if you are not ready to sink most of your free time into it, or if you don't want to worry about money every day. Don't start a company if you don't have self-discipline. And please don't start a company where you are liable with your private cash, it can ruin your life
