with the famly plan do all iPhones /iPads have a appleid ?

No. If a family member has multiple devices (e.g. an iPhone and an iPad) they would use the same Apple ID on each of those devices. There is more information on family sharing in the following: https://www.apple.com/icloud/family-sharing/

But different family members should have different Apple IDs, and I think that's what you were asking.

stevejobsfan0123 wrote:

But different family members should have different Apple IDs, and I think that's what you were asking.

You may be right. The question specifically said "each device" -- but after I replied, I started thinking that maybe I should have said, each device no, each family member yes.