You can’t they are proprietary calls and not shared with the public

retrieving the recorded conversations

What conversations?  If you mean a conversation with AT&T support, those may or may not be recorded and those are for training purposes only, they are not available to customers. 

How do I gain access to the information recorded

You don't 

and all intake of original bill of sale.

You can call AT&T or go to a physical store where you made a purchase, and ask for a reprint of your original receipt.