Dude, you're responding to a 16 year old. At that age, they are literally inventing their identity. As for the "building your brand", everyone is doing that even when they don't know it (consciously or unconsciously). Doing it consciously is because teens are by and large shit scared that they aren't or won't be "good enough", and often they're steered into "standing out" in some way (for nerds, often through academic excellence "with a twist"). They are exhibiting standard behaviour for an envioronment in which there's much more (perceived) demand for "good careers" than (perceived) supply.