God created a man and a woman and called their name Adam (Hebrew generic word for human being). He made the man and then planted a garden for him to live in. The man had access to everything in the garden except one tree. He was given the god-like power of dominion over the earth. As the last act of creation, God created a woman.
Why was the fruit of that one tree forbidden? Because God wanted Adam to obey with his free will. Satan had already fallen from heaven and taken a third of the angelic population with him. I believe that God made Adam to demonstrate to angels that he could make a new kind of being who would choose to obey voluntarily.
Satan tempted the woman. Why the woman? Because she had not experienced the planting and growth of the garden. She had not experienced God's constant presence. God's plan A was for Adam (male and female) to refuse the temptation to eat.
By eating forbidden fruit, Adam chose to obey Satan instead of God. In that way, he committed high treason against God. He still had dominion over the earth, but now exercised it under Satan's authority, not God's. Satan desires only to steal, kill, and destroy.
Meanwhile, God's plan B involves Jesus coming to earth and living a perfect, sinless human live and then suffering our death penalty. He rose again from death and offered restoration of the fellowship of Eden to anyone who would voluntarily acknowledge his Lordship. The completed payoff comes only after Satan's defeat. Meanwhile, we have a down payment, the Holy Spirit.