"Tôi muốn xóa tài khoản khỏi Microsoft Family Safety."

Hello,

To remove an account from Microsoft Family Safety, the steps differ depending on whether you are a child or a parent in the family group.

• If You Are a Child: Unfortunately, child accounts cannot remove themselves from a family group. Only the adult who granted consent for the child account can remove it. You will need to ask the family organizer to sign in to Microsoft Family Safety and remove your account. The organizer can do this by clicking on your name, selecting Remove consent, and then choosing Remove from family group.
• If You Are a Parent: As a parent or family organizer, you can remove yourself or other members from the family group. To remove yourself, sign in to Microsoft Family Safety, click next to your name, and select Leave family group.

For detailed guidance, please refer to the official support article: Leave family group or remove members - Microsoft Support

I hope this helps resolve your issue.

Regards,
Matt | Microsoft Community Moderator.