Jesus is The Creator, Word, God, I AM.
Who is the image of the invisible God, the firstborn of every creature: For by him were all things created, that are in heaven, and that are in earth, visible and invisible, whether [they be] thrones, or dominions, or principalities, or powers: all things were created by him, and for him: And he is before all things, and by him all things consist. – Colossians 1:15-17
And to make all [men] see what [is] the fellowship of the mystery, which from the beginning of the world hath been hid in God, who created all things by Jesus Christ: - Ephesians 3:9
And God said unto Moses, I AM THAT I AM: and he said, Thus shalt thou say unto the children of Israel, I AM hath sent me unto you. – Exodus 3:14
Jesus said unto them, Verily, verily, I say unto you, Before Abraham was, I am. – John 8:58
As soon then as he had said unto them, I am [he], they went backward, and fell to the ground. - John 18:6
For the record, the Most Holy Trinity, Father, Son and Holy Spirit existed from all time and will have no end.
The second person of that Trinity, the Son, became incarnate in the womb of the Virgin Mary and was given the name Jesus, according to the instruction of the angel.
The Incarnation was a historical event and Jesus was a historical person.
Jesus has a birthday. We celebrate it at Christmas. We also celebrate the day of His conception; the day when the Angel Gabriel appeared to Mary and asked for her agreement to God's plan. It's called "The Annunciation" in the Catholic Church.
Prior to the Son taking on human form and coming to Earth, there was no Jesus.
Happy to have helped.