I'm also a late bloomer in this area. I picked up a guitar at 17, but never played with others until many decades later. I started playing guitar with a buddy and then when I moved out of state, I started writing songs and we created a whole rock opera. I did the songwriting, played bass, half the guitar and some keyboards. I also did all the production work, drum tracks etc. I pulled in some more talented people for most of the vocals and more complex guitar solos. I'm not looking to make a second career out of it, so it's all free. But it was an awful lot of fun.
You can download it at www.rock-opera.com or https://soundcloud.com/zurlocker/sets/underground-radio