I knew what I wanted to do when I was 16, then real life happened and I have no idea now.
Honestly unless you are very lucky what you think you want to do at the age of 16 isn't going to be what you want to do later. It's because in the vast majority of the population the part of your brain that deals with introspection (and thus is responsible for answering the question of "what do I want to do with my life?") doesn't even really start to develop until the very late teens/early twenties, and generally doesn't finish developing until the early to mid twenties.
Yeah, I think a lot of people go through this. I said I wanted to get into biomedical engineering to get my family off my back, and fooled myself into it too. It was well before I had any clue what research and academic careers were like; I just wanted something that "made a difference", was new, and came with possible prestige. I think I'd be a pretty unhappy person if I was there today, even if my wages would likely have been worlds better. I think I've always secretly wanted a creative job, and after I started listening to myself instead of everyone else mid-college, I think it's a good fit. Starving artistry is probably the harder way to go, but it's got enough reward and personal challenge, with a decent chance to make a statement or two, and it feels like a good fit
Maybe there's something you threw out as impractical or unlikely too, that you'd be happier with? Try getting in touch with your interests and goals, and thinking about ideal situations or sources of happiness first, and planning your career or future to get you closer to that? Astronaut Chris Hadfield had some wise words that were helpful to me:
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