Music is a fascinating. Below are some are excellent videos that breakdown the concepts of (western) music into its barebones – notes, intervals, keys scales, chords, …etc. Gives you a vocabulary to talk about them.
- Andrew Huang: Learn music theory in half an hour
- 8 steps to understand music theory
- Ross: Understanding music theory in 1 hour
- Guy Michelmore: Music theory in 16 minutes
Another site with some interactive learning: https://www.musictheory.net/lessons