I have two cousins that studied acting (or performance arts, as in theatres). I've always found it hard to imagine how they would survive adulthood with a degree in acting.

Turns out one of them created a small business that does plays for kids at birthdays, and the other one, who is also a musician, is now teaching music and acting at a couple of schools. I'm very proud of them because even though young adults are pushed towards engineering, medicine, economics, etc. they stuck to what they love and they found a way to make it work. They are not rich, but they are independent and do what they love.

I mean I'd say follow your dreams, but I understand your concerns. If you're thinking about this at your age, I'm tempted to think you don't like to improvise in real life. I cannot tell you what to do, but just want to say that whatever you choose, you're allowed to fail, as we all are. It's just a matter of standing up and trying again. IMO that's a big part of adulthood.