When Lucy enters Narnia, the first thing I notice is the music that is played when she first enters. Here I show how to play her song on piano, keyboard, and every instrument on keys in between.
We start from the middle of the piano, and we press E sharp with G at the same time. Quickly, we transition into:
ABCDGF Then slightly getting lower, we do EFEDCE.
Then, we're gonna go into a higher octave, making it sound kind-of princessy. We're gonna repeat it in that octave.
Then, we'll repeat EFEDCE going lower and lower until you can't repeat anymore.
That's Lucy's song, which is quickly followed by "The Battle". Soon, once I've got this song mastered, I'm gonna teach you step-by-step with me actually in view, so it's even simpler than this is to play!