Can my Common App essay be about my life goal?Answered
Can my Common App essay be about my life goal of being a doctor?
Yes it can be about anything as long as it shows your character and reflects who you are. I would be careful with this subject though since it may be too tempting to only talk about your future and not your past (which colleges care a lot about). Thus i would recommend to discuss the experiences that led to this life goal and what caused you to want to go into medicine. I would focus on primarily your experiences and how that has shaped who you are and thus explains why you want to be a doctor.
Agree with @Ree1 that the essay focus should primarily be the experiences that shaped you into who you are & how they influenced your career choice, instead of just talking about how you want to be a doctor. Here's a great video that explains why I think this way & that goes more into detail about this topic: https://www.youtube.com/watch?v=_PhK7n4Labg
The video is great overall but skip to 3:15 if you want to hear the advice regarding tips for writing about having a passion for science/biology/pre-med. Hope this is helpful!