It's honestly hard to gauge because military academies in Battletech work a bit differently than the military academies in the real world (or at least the U.S., where I live).
In the U.S. military academies the cadets are earning a bachelor's degree. Yes, the curriculum tilts in favor of military subjects and topics. Yes they lean into reading military-related works. If you do a google search of "what is required reading at West Point?" you'll find lists. But at its core, they are earning a bachelor's degree.
I just checked West Point's website and I see a pretty healthy range of majors. From chemistry to aeronautical engineering to economics, english, law and legal studies, grand strategy,, Mathematics, foreign languages, Foreign studies of a particular region, and so on. I'm noticing a tilt toward science and engineering majors, not as many Arts majors.
All graduates of a U.S. Military Academy receive the opportunity to become an officer in a branch of the U.S. Military. During their senior year at the academy they learn which branch they will serve in after graduation. After graduation and commissioning they start that training. So that can easily mean months or even years of additional training after earning that bachelor's degree and a commission.
By comparison, most of the Battletech military academies aren't even necessarily teaching officers. Officers are a separate officer training program entirely found within most BTU academies. Most of the academies also aren't offering an education degree but a few do and are called out for doing so. Again leaning to FM: FS for sources, NAIS offers outstanding cadets that opportunity, so does Kilbourne Academy (which hosts a civilian university on-site).
By the time Battletech academy cadets graduate, they've already completed a military specialty program, becoming a qualified mechwarrior, aerospace pilot, infantryman, tanker, engineer and so on. A slice of those cadets have also earned a commission as an officer. (a few academies do ONLY graduate officers, but that seems to be rare)
But that's the U.S. You start looking abroad and other countries do have other models. The real world Sandhurst is an officer program about 44 weeks long, and about 80 percent of the cadets already have degrees. So they spend about a year in an officer training program and then move on to military specialty training.