How do I find a list of my unredeemed Apple Gift Cards?

Your unredeemed Apple Gift Cards will not show up in your Apple Account, you will have to redeem them to show up.

⇢ How to redeem your Apple Gift Card or App Store & iTunes gift card - Apple Support

There is no such list. The ones that have been sent to you by email should show up in your mail account. How you find those really depends upon which mail browser you use.

If these are physical gift cards, those are the equivalent of cash and are not associated with any particular individual. It's only when you redeem them that the entire balance of the card transfers to your personal Apple Account balance and nothing remains on the card.