I feel like plenty of teens and young adults can relate to this post, I don't think I can really give the best advice but I'll try:
What do you like doing? Like hobby wise- Playing video games? Watching youtube vids etc? There's plenty of opportunity to make money from these with the internet- Twitch/yt/etc.. It seems unlikely but if you have the right game plan- it absolutely can happen
Did you ever have a hobby as a kid that you were good at but stopped doing it for whatever reason? Pick it back up and see how it goes.
Drawing was something that I was great at as a kid but quit doing it once I was in high-school. I graduated like a year and a half ago but I recently started drawing again- This sub helps spark my creativity with all the art that gets posted here. I draw manga now, and I have a tattoo gun that I practice with regularly, but drawing isn't my only interest. Like a year ago I found out I like writing-(Like fictional stories and shit) It's super nerdy but idgaf.. I write almost daily now and I plan on being an author one day. Another one of my interests is music, I remember all throughout high school all I did was sell weed and listen to music. I related to plenty of the songs and it eventually spiraled into me wanting to learn how to create music. As of right now, I'm subbed to plenty of music related sub-reddits. I read about it often but I still have a long way to go. For me, the fact that I don't know much motivates me to go learn more. Surrounding yourself with like minded people really important, I would recommend everyone to go read/learn about the things they're interested in. Reddit is a great place to start.
but how exactly do I find out what I passionately want to do in life?
The best I can say to answer this is: think about your past.. What did you enjoy doing when you were younger? Since I don't know you personally I don't exactly know what you're like. If I did I'd probably be able to name a few things. Maybe you played sports as a kid? I wrestled in high school and now I watch MMA religiously, I don't plan on pursuing a career in it but- I'm passionate about it.
My bad for the wall of text...
TL;DR: What do you do for fun? Cross reference that with possible career choices in that field. If you can make a living doing something you like- That's a dream job. Regardless of the pay. Wish the best for you.