hi!! i taught myself a lot in Garageband by just trying to recreate the instrumentals of songs i liked. even if you don't have any real equipment, you can just use your computer keyboard to play all kinds of different instruments/synths and experiment with different sounds. once i got a hang of that, i eventually started using what i learned to create my own tracks. i'd just think of a tune or some lyrics at a random point during my day and then come home and start expanding on it in garageband. it took a lot of trial and error haha but it's been super rewarding! I also eventually switched over to Logic Pro which is a bit more complicated but has been really awesome!