As II understand it, Jesus is eternal, He was never NOT existing. He was with God before the creation of the world. Jesus was begotten not created.

The word monogenes, rendered ‘the One and Only’ in 1:14 by the NIV, is in some other translations rendered ‘only begotten’. That the word should be translated as ‘the One and Only’ is confirmed by its usage elsewhere in the NT, where it is found a total of nine times. It is found three times in the Gospel of Luke: once to describe the ‘one and only son’ of the widow of Nain (Luke 7:12), once to describe the ‘one and only daughter’ of Jairus (Luke 8:42), and once to describe the ‘one and only son’ of the man who sought Jesus’ help for his demon-possessed boy (Luke 9:38). It is found once in Hebrews, where Isaac, whom Abraham was about to sacrifice, is described as his ‘one and only’ son (Heb. 11:17)—in Abraham’s case his one and only son by Sarah. In each of these cases the expression is used to add poignancy to a story by highlighting the fact that it was the person’s ‘one and only’ child who was in dire need, was threatened or had died. The stress is not upon the fact that the person was begotten of the father or mother concerned but upon the fact that the father or mother had only one child and that that child was the one who was so sadly affected. It is found once in 1 John 4:9, where the author emphasizes the fact that the one whom God sent into the world was his ‘one and only’ Son. Once again the emphasis is not that Jesus was ‘begotten’ of God but that God had only one Son, and this ‘one and only’ Son he sent into the world that ‘we might live through him’.
In the Gospel of John monogenes is used in three other places and in each case it is used in relation to Jesus as God’s Son. In 1:18 we are told that ‘No-one has ever seen God, but God the One and Only (monogenes), who is at the Father’s side, has made him known.’ And in 3:16 we find, ‘For God so loved the world that he gave his one and only (ton monogene) Son, that whoever believes in him shall not perish but have eternal life.’ Finally, in 3:18 we read, ‘whoever does not believe stands condemned already because he has not believed in the name of God’s one and only