We are in 2020, when I write this. The common opinion for most of our population is, that money is a very complicated thing. In my opinion money is a solved problem.
To have more money you need to:
Earn more money, than you spend.
This leaves only two variables in the equation. If you want to have more money, you need to earn more, or you need to spend less.
If you have already achieved this, it makes things even less complicated, because you can:
Invest the difference.
The result of a good investment is, that you earn even more money and the interest will compound.