Christ was born of the Virgin Mary because he could have one Father, his heavenly Father. Joseph was the human being appointed by God to care for his Son and mother. To have had a human father, in the eyes of men, would mean that he was not divine.
Christ had intimate knowledge of the Father claiming, "The Father and I are one". (Jn 10:30) And again, "No one knows the Son except the Father, and no one knows the Father except the Son and anyone to whom the Son wishes to reveal him." (Mt 11:27) This kind of intimacy is possible because God is Spirit, the Father and Son have the same nature and are fully aware of one another. We can only be in touch with one another through the senses, but in God there are no sense barriers to the infinite knowledge and love between Father and Son. Perhaps an analogy will help. Did you ever think of how you know yourself? I am self-aware because I have an idea or concept of myself, that is self and self- knowledge. I am distinct from my self-knowledge which is part of me because I am one.
At the Baptism of Christ in the Jordan we read: "As soon as Jesus was baptized, he went up out of the water. At that moment heaven was opened, and he saw the Spirit of God descending like a dove and alighting on him. And a voice from heaven said, 'This is my Son, whom I love; with him I am well pleased.' (Mt 3:16-17) "God the Father represents God. Proceeding from God is God's concept of himself, or his self-knowledge; the self-knowledge of God is what Aquinas thinks of as God the Son. And the Holy Spirit is the relationship of love between God's self-knowledge and God." (Aquinasblog.com)
(Painting by Carlo Dolci, The Agony in the Garden,17th Century)
Someone has asked. "If Jesus was God did he pray to himself when he prayed?" Prayer is a listening to God and a talking to God. Christ is only one person, the divine person and as such was from all eternity in communication (prayer) with the Father. Before raising Lazarus from death "Jesus raised his eyes and said, 'Father, I thank you for hearing me. I know that you always hear me; but because of the crowd here I have said this, that they may believe that you sent me.' (Jn 11:41-42)
In the Garden of Gethsemane Jesus became sorrowful unto death and prayed, My Father, if it is possible, let this cup pass from me; yet, not as I will, but as you will. Christ is a divine person always doing his Father's will, but since he became man he prays through his human nature which was reluctant to suffer an die because human nature instinctively tries to preserve its life. We read, "Although he was a Son, he learned obedience through what he suffered." In other words, Christ had to conform his human will to the will of his Father.
Yes, Christ as the Son of Father was one with the Father in all things but now his human nature had be brought into this unity and so he always prayed to Father.