Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Yes, One subscription can be shared with up to 6 people (including the purchaser).
Each person uses their own Microsoft account.
Each person gets their own:
Word, Excel, PowerPoint, Outlook, OneNote, etc.
1 TB of OneDrive storage.
Personal settings and files.
Each person can install the apps on multiple devices.
So in your situation:
Parent/admin account = subscription owner.
Four additional household members = invited to share the subscription.
Total users = 5, which is within the 6-person limit.