God used people to write the Bible but God also guided them to write what he wanted them to write.

(Jude 1:3 NIV) Dear friends, although I was very eager to write to you about the salvation we share, I felt I had to write and urge you to contend for the faith that was once for all entrusted to the saints.

There were false gods in every culture on earth. It doesn't matter that they existed before Christianity. God revealed himself to man going back to the time of Adam.

There's no culture on earth millions of years old. You're mistaken.

Jesus wasn't wrong about anything. Jesus was God. Jesus existed in Heaven before he was born as a child in Bethlehem. Jesus is back with God. Someday he will return to rule the earth.

(John 17:4-5 NIV) I have brought you glory on earth by completing the work you gave me to do. {5} And now, Father, glorify me in your presence with the glory I had with you before the world began.

(Daniel 7:13-14 NIV) "In my vision at night I looked, and there before me was one like a son of man, coming with the clouds of heaven. He approached the Ancient of Days and was led into his presence. {14} He was given authority, glory and sovereign power; all peoples, nations and men of every language worshiped him. His dominion is an everlasting dominion that will not pass away, and his kingdom is one that will never be destroyed.