Harsh but True
If you don't have the conditions, you should only learn investment knowledge in the evenings. Don't wander around with the dream of getting rich quick, rich even faster. Focus on doing something professionally, doing manual labor, learn how to make money first. This money should not be earned from investing, gambling, or trading. It should come from hard work, no matter what field.
Earn and save money as much as possible, only when you have enough capital, think about investing, compound interest. 300 million is not a difficult or hopeless number when you work hard and save. That is the first challenge you need to achieve: Having capital.
Trading / Short-term trading can be a way to earn capital. But they have never been effective. Its success rate is not even 8%. In a big uptrend, you can take advantage of them. But that's an opportunity that doesn't always come around. Under normal conditions, work and save to earn capital.
In fact, 200 - 300 million is still just a number for you to get used to investing. Anyway, you need at least 1 - 2 years to gain basic knowledge and methods. This is also the time for you to continue to accumulate more capital and gain basic skills for practice later.