Be the first to complete this puzzle, and join me in a future video [Part 1]

This is only part 1. Part 2 will be privately released to those who completed part 1 exactly one week after the first person completes part 1.

You'll need this later: csx42#4476
Discussion:

==============================================

Hints:

Some music theory knowledge is required.

abcdefghijklmnopqrstuvwxyz

There are 7 diatonic chords in a minor key.
There are 26 letters in the alphabet.

0 1 2 3 4 5
1 2 3 4 5 6

1 2 3 4 5 10 11...
1 2 3 4 5 6 7 8 9 10 11...

==============================================

Good luck.

[Part