Sounds like you have your school sights set way too high. An alternative is a community college the first two years and then transfer into a 4 year in-state school with your favorite ROTC,.
Good answer. Sounds like OP's parents are drinking the KoolAid of prestigious U being a golden ticket to life... having attended Stanford and UCLA myself, and working with business owners in CA across the spectrum of industires, I can assure you that success in business, and even moreso life, has more to do with your work ethic, problem solving ability, and attitude than any degree hanging on the wall. Suggest you read the book "Harvard, Schmarvard", or better yet, google Krueger-Dale II and read their conclusions ten years ago, and recently updated, that conclude that business success has no correlation to which college a person attended... and everything to do with how impressive they were at age 17 that made those colleges accept him/her.
Back to your issue of "how to commission":
1) Academy
2) Rotc with scholarship
3a) if you have $$, ROTC without Scholarship
3b) if no $$, then Junior College, then in-state U, joining ROTC no scholarship
3c) if no $$, enlist in Army National Guard, or Army Reserves, take the $5k up to $10k per year in incentives, and participate in ROTC in the SMP program at a 4yr in-state U.
4a) begin college, and re-apply to the all four Academies as a college Freshman. Take Calculus, Chemistry and any other course that Academy freshmen typically take, do well in them, and hopefully get accepted to the Academy a year later than you would have out of High School. Participate in ROTC. Get a Nom from the ROTC PMS/PNS
4b) for Naval Academy ONLY, begin college per 4a), but do NOT participate in NROTC. Reapply to the Naval Academy with the rest of the HS seniors.
5) upon graduating college without participating in ROTC, apply for Officer Candidate School
6) enlist now, work hard, get promoted, and apply to ROTC out of the enlisted ranks
7) enlist now, work hard, get promoted, and apply to the Academy out of the enlisted ranks. If I recall correctly, there are about 150 slots at the Academy reserved for Enlisted, and those slots are never fully taken.
8) Stay enlisted, work your way up, and become a non-commissioned officer that way
there are many ways to skin a cat. Explore all options.