A:AnswerIf your warranty is Apple Care, contact Apple. If it is a Best Buy Warranty contact Geek Squad. Might I suggest after it is repaired you get a "Hard Glass" (Brand Name) or equivalent screen protector? It is well worth the cost.
A:AnswerYes it does. On a day I was feeling generous I gave my iPad Pro to my son. If the plan didn't follow I would not have given him the iPad Pro because he is not always great with making sure things are safe.
A:AnswerUnfortunately no. AppleCare needs to be purchased at the same time as your iPad so that it can be registered together. You may still be able to purchase it through Apple directly, just not through authorized dealers separately.
A:AnswerIs link to your phone number you provided if you ever need a physical copy just go to any Best Buy or look it up on the website by login in to your account and search purchase history.
A:AnswerYes, you will have to create either a Family Apple ID or an individual ID for her. And to my knowledge Apple care is linked to the iPad serial number and purchase order. Send her a gift receipt or keep a copy and you will be Ok.