If you had the chance to invest in the stock market without placing any of your own money up for risk, that would be the ultimate opportunity! Although you're not using real money, simulators and demo accounts provide an important tool to learn about investing in stocks, or trading foreign currency.
Practice, practice, and more practice, in addition to research is the key to learn. If you're interested in learning how to trade stock, you can practice on the Investopedia Stock Market simulator. Have fun!