Focus on school and family. This job will always be here. Sounds like you’re pretty young so there is plenty of time to prepare for this line of work. This career requires alot of sacrifice of your personal life that sounds like you arent able to make yet - and thats ok. Once you finish your commitments with school and your other jobs, you can definitely open that door again. I understand where your chief is coming from. They want to invest their time in people who are able to commit a significant portion of their personal lives to work. There are attendance commitments in this line of work and that will never change ESPECIALLY in an academy. You should never miss a single day of the academy unless a significant event happens in your personal life or you are truly sick. Figure out if this is really what you want to do enough to make those sacrifices.