To get your song on iTunes, you can use a music distribution service like **TuneCore**. Here are the steps:

1. Sign up for a TuneCore account.
2. Select the type of release you want to get on iTunes: single or album.
3. Upload your music and cover art to put your songs on iTunes.
4. Add music contributors so they get credited when your songs are sold.

You can also purchase songs by going into the iTunes Store. If you don’t see the store listed in the sidebar menu in Music:
- Click Music in the menu bar at the top of the screen, then click Preferences or Settings.
- Open the General tab and check the box next to iTunes Store next to the Show header.

If you want to download purchased songs from iTunes, you can do so using the Apple Music or iTunes app. To download from Apple Music:
- On your iOS device, launch Apple Music, and at the bottom-left corner select the “Library” icon.
- Select either “Artists,” “Albums,” or “Songs.”

I hope this helps!