How can i be an officer in the mil ( any branch)?

I want to be an officer in the mil. and i just want to know my fastest rout. I'm currently in the navy as a corpsman. I have a few college credits but i feel like i have no set goals. I understand that there is no way for you guys to tell me what i want to do with my life but being an officer in the military is what i know i want to be but in what field i have no clue i would like to be a dentist ( seeing as i am a dental tech now I'm used to it) but the 900 years of school is going to be tough. any suggestions on an easy field to become and officer in?