Hi m99kelley
welcome to the Apple (user-to-user) Community.
Re: "Can I use my ipod nano (7th gen) in the same way I used it with iTunes,
even though I've converted to MacBook Air and Ventura 13.6?"
Apple support do have this article online:
Use iTunes to sync your iPhone, iPad, or iPod with your computer - Apple Support
Apple Support also have another article online that may be helpful:
Use Sync Library to access your music library across your devices – Apple Support
Eg: says:
"Access your music library on other devices
After you turn on Sync Library on your Mac, PC, iPhone, or iPad, you can access your music library on any device that has the Apple Music app. Just make sure that your device is signed in with the same Apple ID that you use with your Apple Music subscription. You can also access your music library on music.apple.com."
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Re: Can I use Apple Music for Android on my phone with an Apple music subscription
Apple Support's article: How to: Join Apple Music on Android
says:
Subscribe to Apple Music on your Android device to stream millions of songs
or
If you already subscribe to Apple Music
- On your Android device, download the Apple Music app from Google Play.
- Open the Apple Music app.
- If you see an offer for a trial, tap Sign In in the upper-right corner. Or tap the More button
, then tap Sign In. - Enter the same Apple ID and password that you use with Apple Music.
Learn how to sign in to Apple Music on your other devices with the Apple Music app.
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More info:
How to: Listen to Apple Music on the web and in apps - Apple Support
How to: Redownload music - Apple Support
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If needed:
Music Support Website has info. and contact options:
(There's a "get Support" link at the bottom of the webpage below:)
Music - Official Apple Support
All the best :-)