How much space can be shared under Family Sharing in iCloud?

Hi.

I use 2TB Space on iCloud and have Family sharing turned on. Had a few quick questions:

1. Whats the maximum space that I can share with family members out of that 2 TB? I saw wife automatically got 5-6ish GB but she needs more. How do I make it happen?
2. If I am the primary user does this automatically give me access to their iCloud storage that they share from me?
3. If I share an album with one of my family members does the shared album take additional space at their allotted quota? Or are they just able to view/edit the source album in my iCloud?

The questions may be basic, sorry, I am a new user and trying to find my way.

Thanks!