How to buy storage for my child's cloud? the child's profile says he needs to ask an adult to help make this purchase, but it does not say how the adult can actually make the purchase

Hi Lisa,

Good day. You just need to purchase the storage from your adult MS account. You just need to have Microsoft 365 Family, and from it you just need to share your subscription with your child. Each person you share it will get their own 1 TB of OneDrive Storage. If your child already has 1 TB and needs more, the additional storage has to be purchased by the Microsoft 365 subscription holder. Microsoft currently doesn’t allow the child account to purchase additional OneDrive storage itself.

1. Sign in to the adult/parent Microsoft account that owns the Microsoft 365 subscription.
2. Open the Microsoft storage page and select Manage storage or Upgrade.
3. Choose the additional OneDrive storage option you want and complete the purchase.
4. If you have Microsoft 365 Family, you can also share the included 1 TB OneDrive storage with your child.

You can check this link for available options:

https://support.microsoft.com/onedrive/microsoft-storage-faqs

I hope this helps.

Regards,
Jhun