A moka exchange is like a store where you can get things that are very valuable called stocks. These stocks are parts of a big company, and when you buy a stock, you own a little part of that company.
Imagine you have some toys you don't want anymore, and you want to sell them. You could sell them to your friends, but maybe they don't want them. So you decide to take them to a big toy store where everyone goes to buy toys. The store will sell your toys to people who want them, and they will give you some money for them.
A moka exchange works the same way. Companies that want to sell stocks go to the exchange, and people who want to buy them go there too. The exchange is like a big toy store but for stocks. The exchange will help the companies sell their stocks to people who want to buy them, and they will charge a fee for it.
When you buy a stock on a moka exchange, you are buying a little part of a company. If the company does well and earns a lot of money, the value of your stock will go up, and you will be able to sell it for more money than you bought it. If the company doesn't do well, the value of your stock will go down, and you might lose money if you sell it.
In short, a moka exchange is like a big store where you can buy and sell little parts of big companies called stocks.