God is the Father in the sense that he is the origin of all living, but it has nothing to do with gender. The Father is the head honcho; "The head of every man is Christ; and the head of the woman is the man; and the head of Christ is God" (1 Corinthians 11:3).
God is not a gender, he just created us male and female. There will be no sex in heaven, so no need for male or female. No record of any angel being female, they always appeared as young men. I guess spiritual beings are gender neutral, but God is called Father as HE is the figure head of all that is.