The Sons pre existence in John’s gospel. There are dozens of other scriptures in other places verifying the Eternal existence of the Son.
John 1:1-3
In the beginning was the Word, and the Word was with God, and the Word was God. He was in the beginning with God.
All things came into being by Him, and apart from Him nothing came into being that has come into being.
John 1:14
14 And the Word became flesh, and dwelt among us, and we beheld His glory
These verses in John’s prologue reveal the pre existence of the Eternal Word/Son who was God and became flesh. He was the Creator of all things. Nothing came into existence apart from Him. He is before everything that has a beginning.
John 1:15
15 John bore witness of Him, and cried out, saying, "This was He of whom I said, 'He who comes after me has a higher rank than I, for He existed before me.'"
John 1:30
"This is He on behalf of whom I said, 'After me comes a Man who has a higher rank than I, for He existed before me.'
John the Baptist was 6 months older than Jesus Christ. So it is impossible for Christ to be before him unless Jesus pre existed.
John 3:13
No one has ever gone into heaven except the one who came from heaven — the Son of Man.
Again we see the pre existence of the Son and where He declares that He came from heaven to earth.
John 3:17
"For God did not send the Son into the world to judge the world, but that the world should be saved through Him.
This verse shows the Son was sent from heaven by the Father to the earth.
John 6:38
For I have come down from heaven, not to do my own will but the will of him who sent me.
Human beings come into existence when they are born into this world, but we surely do not come from Heaven.
John 8:23
"You are from beneath I Am from above, you are of this world I Am not of this world"
John 8:58
Jesus said to them, "Truly, truly, I say to you, before Abraham was born, I Am."
Here we see that Jesus lets the Pharisees know that He existed as a person before Abraham was born. Once again we see Jesus claiming to be the Eternal God.
John 16:28 I came forth from the Father, and am come into the world: again, I leave the world, and go to the Father.
John 17:1,5
“Father, the hour has come; glorify Your Son, that the Son may glorify You,
And now, Father, glorify Me in your own presence with the glory that I had with you before the world existed.
Here we see the Son declared that He shared the same Glory together with the Father prior to creation. This passage makes Him equal with the Father as the Eternal God. Below again we see His pre existence and in 17:25 Jesus again states the Father sent the Son into the world
John 17:24
"Father, I desire that they also, whom Thou hast given Me, be with Me where I am, in order that they may behold My glory, which Thou hast given Me; for Thou didst love Me before the foundation of the world.
hope this helps !!!