Family Sharing

You cannot selectively share with individuals other than to not have them in the family at all. However, as observed by Demo, you can disable sharing of individual subscriptions for all family members, you just can't pick on person and not another. That seems to be what you're asking.

Yes. You can pick and choose the subscriptions that you want to share with your family. You don’t have to share iCloud storage if you don’t want to do so.

I believe that I misunderstood what you were asking. I apologize. Please read Limnos’s response.