iCloud storage switching from individual to family
How do I make sure my photos will automatically be stored in family shared 2TB iCloud account once my individual iCloud account expires?
Question marked as
Top-ranking reply
Your photos and other data stay where they are and continue to be accessed using your Apple ID the same way they always were. The only things that change are the amount of storage available and the billing.
Also see Share iCloud+ with your family - Apple Support including the excerpt below:
When you share an iCloud+ subscription, everyone in the family group uses their own account. That way your photos, documents, and other information stay private, even though you're sharing access to the service. You simply share the features and space available in iCloud+ with your family members, so you only have one plan to manage.