Most people have full-time jobs. Most people do not like their full-time jobs. Most people would rather spend their time doing something else. How do you spend your time?
How can you use your free time to generate income? That is what a side hustle is. If you can manage a good side Hustle, all of that money that you make you can save. And overtime grow a large enough amount to invest in something that you are really really passionate about.