If you are interested in trading, what you will likely cultivate in your mind is profit-making to generate more income for yourself. People don't trade because they want to have fun; they trade because they only want to make profit. Despite that, traders encounter losses too, but their sole purpose in trading is for profit sake.
There is a lot of misleading information about trading on the internet, both on YouTube and on some other sites. Maybe your friends might have handled trading in the wrong manner, and that's why he has lost that amount of money. A trader must learn and develop some trading strategies for themselves that can help them play it safe while trading. Trading is risky, and as a trader, you don't have to invest all your capital in it; just invest the amount that will not put you in psychological trouble when the trade fails.
Buying Bitcoin is very good, and it's good advice you have, but telling someone to use all their wealth to buy Bitcoin is not acceptable advice. Although the percentage of profit will be very high if someone invests a very large amount, yet, it's not wise for one to just have all their money in one investment. While making an investment, you have to keep some funds as emergency funds, and if your money is too large to be invested in another asset, you should invest in another asset too, so that you are secure with two different forms of investment. If one doesn't yield the expected results, the other one will.