Apple Music is not automatically shareable through Family Sharing. You would need to subscribe to the (higher priced) Apple Music Family plan, instead of the Apple Music Individual plan. [Compare plans]
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When you subscribe to Apple Music Family, (or Apple One Family, or Apple One Premier,) you can use Family Sharing to share Apple Music with up to five other family members. Your family group doesn’t need to do anything — Apple Music is available to them the first time they open the Music app after your subscription begins, or when a subscriber joined the group.
In a Family Sharing group, the subscription only shows for the subscriber. The other group members are not actually subscribed, but can make use of the subscription on their own account by being part of the group. It would be listed in their Family Sharing settings that Apple Music is shared with them. The other group members build their own library, playlist, and such, independently of the subscriber.
Family Sharing doesn’t work internationally. All group members should have their Apple ID account configured for the same country or country-like region.