True, but not a lot. The hard part for most is getting started. So, where does the initial money come from? You either borrow it or earn it; and it is nearly impossible to borrow money before earning any (except for debt slavery of student loans) unless it’s from a family member. That is often a risky proposition for the lender as it is loaned with the hope of helping you prior to you taking the initiative to do anything for yourself. It also teaches you to depend on the hard work and goodwill of others without sacrificing your own time and energy. But, if you are responsible, have a great plan, and are blessed with a good family, it can work.
The most reliable way to make money is to earn it: work longer hours, extra shifts, overtime, take a second job, or change jobs to one with higher pay (more education or experience required.) The most reliable way to keep more of the money you earn is by creating and sticking to a budget, spending less than you make, and reducing expenses. Each of these topics will eventually have their own post. This is easier for young people and those without families. Unfortunately, many make adult decisions without the maturity to consider or handle the consequences.
This is what is known as Opportunity Cost: The loss of potential gain from one alternative by pursing another. You should deliberately choose the path with the most potential and avoid poor choices with long-term consequences. This concept applies to areas outside investing. Student loan debt vs. service in the military to earn the G.I. Bill, drugs and alcohol, dropping out of school, not going to college, and sex outside of marriage resulting in single motherhood; good and bad choices dramatically broaden or narrow life outcomes.
If you are young, live at home as long as possible to save money. If you must move out, consider renting a single room from an elderly couple. It is far cheaper than getting your own place and they often need help, enjoy the company, and include a free dinner meal. If you are not going to attend college, get paid while learning a trade. That way you are building a career and not simply working a job with no upward mobility. If you start in fast food, pay attention and perform as many of the functions as possible. Learn to cook, cashier, and team lead a shift. If you can manage a fast food restaurant, you can learn to manage anything.
Undecided? Consider joining the military; free health care, free food, free lodging. Choose an MOS that gives you a useful life skill; it may lead to an excellent civilian job. Use tuition assistance while in and get a jump on college. You should be able to exit in 3 years with $10K saved and a reliable car paid off. Then, the G.I. Bill actually pays you a living stipend to attend college. I caution against marrying a local gal because you are lonely and away from home for the first time. That is the quickest way to screw up your long-term plan and is frequently why soldiers reenlist and never go to school.
Think outside the box. Develop a side-hustle based on your hobbies. Playing in a band is not the only way to make money in music. There is also teaching, song writing, and producing. It is similar with sports. You can coach, referee, run a camp, or do personal training. Heck, start a YouTube channel. These endeavors are often the most satisfying as they align with your passion and don’t feel much like work. PewDie Pie made a fortune playing video games.