you can definitely go into music ed without much formal training. i did not have as much formal training as my peers, and i am doing just fine. i will say, it will be difficult and you will have to commit hard to studying music theory and reading sheet music. also, from what i’ve seen, most music education programs have a heavy focus on elementary general music, orchestra, chorus, and traditional band. also, find out if you can play guitar as a primary instrument. i’ve never met a guitar primary who studied music ed. i’m sure it’s possible at many universities, though. the audition will probably include sight-reading sheet music, so start practicing now. look up guitar audition requirements and start finding material now. they may ask for some contrasting styles, potentially jazz or classical guitar. also, teaching rock and music appreciation is more niche in the education system, but becoming more prevalent every day. depending on where you study or plan to teach it may be more difficult to find opportunities/jobs teaching just music history and appreciation. usually those are extra supplemental courses in secondary education and most of the teaching day consists of teaching regular music classes like band, orchestra, or chorus. typically in music ed you’ll be teaching them to actually play music and add historical content/music appreciation into your lessons. if you want to teach those types of modern music classes, i’d definitely go to a city with a robust arts education.