How to sync iCloud Photos across multiple Apple devices?

Hi, I want to use the cloud to manage 2 iphones, macbook and ipad.

The two iphones are mine and my wifes and we wish the photos to be taken to be seen on all devices.

Shared albums say that it can only be up to 5000 but i want us to be able to see all photos, approx 65000.

Is there a way that any photos taken are automatically added to the cloud and then able to see and manage these from all devices?

In addition to this I need to back up all devices but that can be on different accounts.

Currently using Mylio, although good it doesn’t really work for me.

Thank you

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