
Ronald A. answered 12/15/19
Essential Skills for the Musician
You seem to have already formulated the answer to your own question. To write songs, you have to learn how music works.
The only thing I would add is that yo don’t have to wait for any thing to begin writing songs. Some very effective songs have only one (1) chord and simple melodies.
So .... As you learn your instrument, write songs to exercise everything you learn about your instrument or about music. That’s what the Beatles did!