In the Old Testament, only angels are described as literally living in heaven with God. For example, an angel calls to Abraham from heaven (Genesis 22:11,15).
Jacob has a vision of angels descending and ascending on a staircase between heaven and earth (Genesis 28:12), showing that angels are actively involved in events on earth and in heaven. The New Testament also talks about the “angels in heaven” (e.g., Matthew 18:10; 22:30; 24:36).
In the New Testament, Jesus was added to the population of heaven when he ascended (Acts 1:9). Later, Stephen saw him there:
But he [Stephen], full of the Holy Spirit, gazed into heaven and saw the glory of God, and Jesus standing at the right hand of God. (Acts 7:55)
The Bible also makes it clear that no other human being has ever gone to heaven.
The heavens are the Lord’s heavens,
but the earth he has given to the children of man. (Psalm 115:16)
No one has ascended into heaven except he who descended from heaven, the Son of Man. (John 3:13)
However, there are also some verses that use “heaven” symbolically which sometimes confuse people who read them literally. For example, Isaiah 14:12 describes the King of Babylon “falling from heaven”:
“How you are fallen from heaven,
O Day Star, son of Dawn!
How you are cut down to the ground,
you who laid the nations low!
Here, “heaven” is used to mean a high position of power. The king had been overthrown by the invading Persians and was now as low as any other person on “earth”.
For more on angels, see Angels: God’s servants.