Imagine what Bitcoin was like 10 years ago and now imagine what Bitcoin has become. So invest directly in Bitcoin without considering any aspect, you will get much more success in it but of course you have to have a long-term plan for your investment.
Honestly, I think it is inappropriate and no longer true to take bitcoin's achievements, what has happened in the past to give advice to others or rely on it to predict the future. I mean in the last 10 years bitcoin has grown millions of percent and made many people rich with minimal capital. While bitcoin's potential remains, that doesn't mean the same thing will happen again. We cannot expect bitcoin to increase by millions of percent in the next 10 years when its capitalization has reached trillions of dollars, not just a few hundred million dollars like 10 years ago. This type of advice can be misleading to beginners if not explained clearly.
Giving financial advice to others is not an easy task, at least we must know clearly their financial situation, investment horizon and goals. We can't give random advice when we don't even have specific information from him.
If he only has $10 or $20, and that's the only money he has, what's the benefit of investing in bitcoin?