Investing in your card business
There are many ways to invest money. Investing means that you spend some type of a resource like time or money because you believe that you will get a reward that will increase either your resources or capabilities.
Buying this BizzyBox System was an investment. Someone spent money to purchase this course. With this course you gained a lot of resources (Cards, Envelopes, Crayons, and Stickers) and you also grew your capabilities (Learned to run the business and draw new pictures).
When you sell all of your cards you will have used all of your resources. If you want to continue earning money you will need to invest some of your money in new materials.
New Business
There are tons of other businesses that you can start. The question is do you have the capabilities and resources to start them.
Do you have enough money?
Do you have the skills?
Do you have the materials?
For example if you want to start a lawn mowing business you need to have a lawn mower and you need to be old enough to use it.
Stock Market
When you invest in stocks you are investing in companies that already exist. A stock is a small piece of a company. You can buy stock in companies like Disney and Apple. By owning a piece of the company you also get part of what they earn.