I wanted to be an astronaut at the age of 12 because from the age of 6 to probably 13, Apollo 13 was my favorite movie. Of all time. Of all time. Serious though, it was. 
And what now, dad? All I’m doing is teaching guitar with you and not doing shit because I have no clue what to do. Am I doing my 12 year old plans?
Just because you knew who you wanted to be since you were a kid doesn’t mean that it applies to everyone else around you.