how do i update my intunes on my mac?

Hi,

https://support.apple.com/en-ie/HT201352

On your Mac

If you update your Mac to macOS Catalina or later, you can access your iTunes media library in the Apple Music app, Apple TV app, Apple Books app, and Apple Podcasts app. To manually back up, restore, or sync your iPhone, iPad, or iPod touch, use Finder.

If you can’t update to the latest version of macOS

You can update to the latest version of iTunes (up to iTunes 12.8).

1. Open the App Store on your Mac.
2. Click Updates at the top of the App Store window.
3. If any iTunes updates are available, click Install.