There are also verses in the New Testament that clearly speak of “God” being the“God” of Jesus Christ. Romans 15:6 says “...you can, with one mouth, glorify the God and Father of our Lord Jesus Christ.” 2 Corinthians 1:3, Ephesians 1:3, and 1 Peter 1:3 all say “Blessed be the God and Father of our Lord Jesus Christ.” So the “one God and Father” (Ephesians 4:6) is the God of Jesus Christ. The “one God” of the Bible never says He has a God because He is God, the Father, the Creator, “the Most High God” and He has no equals. Jesus is not “God” because he's a man, the last Adam, the created Son of God, and the God of Jesus is God the Father.
In John 5:44 Jesus called the Father “the only God” and The New American Standard Bible goes so far as to translate it as “the one and only God.” The straightforward reading of this verse is that Jesus did not think of himself as God. Jesus prayed to God on the night he was arrested that people would “know you, the only true God”(John 17:3). It seems disingenuous or at least confusing that Jesus would refer to his Father as “the only true God” if he knew that both he and “the Holy Spirit” were also “Persons” in a triune God and that the Father shared His position as “God” with them. It seems much more likely that Jesus spoke the simple truth when he called his Father “the only true God."
Colossians 1:15 calls Jesus “the firstborn of all creation.” Scholars disagree on what this phrase means, but that is primarily because the doctrine of the Trinity obscures its simple meaning. Trinitarian doctrine states that Jesus is “eternal” but if that is true then he cannot be the firstborn “of all creation” because that would make him part of the creation. But the simple reading of Colossians 1:15 seems clear: Jesus is a created being. The BDAG Greek-English lexicon [entry under “creation”] explains the Greek word translated “creation”as “that which is created… of individual things or beings created, creature.” Not only was Jesus a created being, but he's also called the “firstborn” from the dead because he was the first one in God’s creation who was raised from the dead to everlasting life—a point that is also made in Colossians 1:18.
God is eternal and was not born. In contrast to the eternal God, Christ is “begotten” that is born meaning Jesus Christ had a beginning. Jesus is never called “God the Son” in the Bible, but he's called the “Son of God”more than 50 times, and a “son” has a beginning. The very fact that Jesus is the “Son of God” shows he had a beginning. Trinitarian doctrine denies this and invents the phrase “eternally begotten" but “eternally begotten” is not in the Bible, but was invented to help explain the Trinity and is actually a nonsensical phrase because the words are placed together but they cancel each other out. “Eternal” means without beginning or end and something that is “begotten” by definition has a beginning.
Did you notice Hebrews 1:8? "But of the Son, He (God) says, 'Your throne, O God, is forever and ever ... Therefore God, Your God, has anointed You with the oil of gladness.' " So here we have God calling His Son "God".
Also in John 5:18, the apostle John tells us that Jesus made "Himself equal with God" - "... but also was calling God His own Father, making Himself equal with God."
I notice in John 17:3, you conveniently left out the last phrase. "This is eternal life, that they may know You, the only true God, AND JESUS CHRIST WHOM YOU HAVE SENT." So eternal life is knowing the Father AND the Son. Regarding Jesus' prayer to His Father, it really doesn't matter that "it seems disingenuous or at least confusing" to you that Jesus would refer to His Father as "the only true God". God never promised that the makeup of His own person or persons would be totally understandable to us. In fact, it makes more sense that the person of the God of all creation would be incomprehensible vs. a Being that we can explain and understand.
Psalm 2:7 (" ... You are My Son, today I have begotten You.") is quoted by Paul in Acts13:32-34. There Paul clearly explains the verse in Psalms. He says that "today I have begotten You" refers to the Father raising His Son Jesus from the dead.
You said that Jesus "was the first one in God's creation who was raised from the dead to everlasting life." That's true but we must also mention that He was the first to receive a glorified body when He was raised. ALL the other godly men and women since creation who have died and gone on to heaven, still do not have a glorified body, which is described in 1 Corinthians 15:42-44. They must wait for the 2nd Coming to receive their glorified bodies.
So the "firstborn of all creation" Col. 1:15 and the "firstborn from the dead" mean the same thing - that Jesus was the first person raised from the dead to receive a glorified body. Several persons were raised from the dead before Jesus was raised, but they returned to their original bodies. The gospels and Acts record several of these. Not Jesus - He alone has a glorified body, but when He returns, we will also be getting our new bodies.
When God became a man - that is, when the Word who was God (John 1:1) became flesh (John 1:14), He is called "the only begotten from the Father". This baby was given the name Jesus. Prior to His birth, He was called "the Word", which was in fact God. At His birth, He was also called the Son of God. We don't have any Old Testament appearance of the words "the Son of God" or even "the Word of God".
Jesus made it clear that He pre-existed. John 17:5 "Now Father, glorify Me together with Yourself, with the glory which I had with You BEFORE THE WORLD WAS." However, in His pre-existence, He was not called Jesus - apparently He was called the Word, even though the Old Testament never uses that title.
John the Baptist tells us that Jesus existed before he did, even though John was born six months before Jesus. John 1:30
Jesus Himself tells us He pre-existed: John 3:13; John 6:33,38, 62; John 8:23; John 16:28
Jesus, as the begotten Son of God had a beginning in Bethlehem, when Mary was impregnated by the Holy Spirit. But the spirit of Jesus existed from all eternity - He was the Word, He was God. He was the only begotten of the Father. God never impregnated Mary or any other woman again. When Jesus tells us He existed before, we understand that He was not called Jesus at that time.