Under no circumstances should you invest money you can't afford to lose or that you'll need in the near future. With crypto, this is essential because prices can swing wildly - your buddy might've gotten lucky with the timing, but he could just as easily have lost money instead. If you're new to this, try to understand how Bitcoin actually works and why the price fluctuates before you put real money into it. A lot of beginners buy at the peak when everyone's talking about it, then panic-sell when it drops.
Honestly, nobody can answer the question "is it still worth it?" Some people say Bitcoin's too late to get into, others see huge potential. Nobody knows what's right. If you still want to jump in, do it with small amounts that won't keep you up at night if they disappear. And put the money in without constantly checking the price - it's just psychologically easier that way.
Alternatively, you could mess around with free simulators or paper trading first to get a feel for it. Books or YouTube videos help too, so you're not investing blind. In the end, it's your call - but make it deliberately, not just because your buddy made money.