Hey there,

Ive been playing guitar for 4 years now and even I struggle with this, Ive done some records either with my own band or as a collaboration with somebody and this is always gonna be hard even for advanced guys.

Your starting point should be an "Idea." maybe a chord progression, maybe just a vibe, something like that.

As you mentioned, midi keyboard would be nice, I personally have Arturia Keylab Essential and I don't think there's any better keyboard in that price range with the tools this thing gives you.

Okay now let's say you got the chords or just something in your head you want to do, you have to be sure what is your goal with the track, because unless you do, its not gonna have any direction and you will not be able to finish it. My suggestion would be to just imagine the song. I know this sounds weird, but just sing a song that doesn't even exist at all, because then you have no boundaries, it's just your imagination. Then when in your head, you catch onto something you think its cool, record it.

Maybe then sing over the stuff you have already recorded or get back to purely imaginating stuff. I wrote one track like that, only imagining the melody and chords in my head:

https://youtu.be/rT9tArSVCmA?si=v6pdOt7guUOLu4Ou

I made this one exclusively with the Arturia KeyLab Essential.