Q: iCloud Library Confusion

Hello All,

I'm probably asking a dumb question here, but I just cannot get my head around this?

1. On my PC, I add a track to my iTunes from Apple Music.

2. Within seconds, it adds the track to my iPhone via Wi-Fi/Cloud; the phone is not plugged in.

3. On my PC, I then download the recently added track. It downloads OK.

If I sync my phone with My Music, is it meant to upload the song to my phone or am I also meant to download the song on my phone again?

I would expect that iTunes PC would sync and upload to my phone?

That make sense?

Cheers

Jack