How Do You Find Out Who Your Biological Father Is?

Amber and her half sister, catlan, decided they wanted to find out who their biological father was. Amber tried to reach out to the clinic where she was conceived but it no longer exists. They contacted them through 23 and me; one of them eventually responded to a 23 and me message,. And once we were connected on facebook, it was through searching their mutual friends that i was able to find kurt. Now, who is kurt? Kurt is my biological father.