Good afternoon devy02,
Welcome to the Apple Support Communities!
It sounds like you are unable to add a person to your Family Sharing group, and we'd like to help.
Are you the organizer of the Family Group? Which Apple device are you using to manage Family Sharing? What iOS version is running on this device?
Can you describe what happens when you try to add the person having the issue to your Family Group?
Do they receive your invitation?
What error message do they see when they try to accept it?
The resource you viewed - Use Family Sharing with Apple Music on Android - is the correct article for what you are trying to do.
"Accept an invite to a family group and share their Apple Music subscription
- On your Android device, open the email invite to join Family Sharing.
- Tap the link in the email invite.
- In the "Open with" screen, tap Apple Music.
- Tap Accept.
- Sign in with your Apple ID and password."
Set up Family Sharing
"If your family member already has an Apple ID, follow the steps below to add someone to your family group.
If your family member is with you, they can enter their Apple ID password on your device to accept the invitation. You can also send them an invitation and they can accept it from their device.
If you can't accept the invitation, check if someone else has joined a family with your Apple ID. Remember, you can only join one family at a time, and you can only switch to a different family group once per year."
If the issue persists, please reply to this thread and we'll do our best to help you!
Take care.