For a long time people have thought that the Word is a separate person
That's because the designation "the Word" is simply another name of the Son of God, due to His function and role as the Son, and Highest Messenger of the Father, and we see Him as such even in Genesis, as "the voice [the Word] of the LORD [Father]" that is walking in the Garden with Adam and Eve.
Gen 3:8 And they heard
the voice of the LORD God walking in the garden in the cool of the day: and Adam and his wife hid themselves from the presence of the LORD God amongst the trees of the garden.
Further in Genesis 1:1 is the Aleph-Tav (Alpha-Omega), to which John in John 1:1 refers to.
Gen 1:1 בראשׁית ברא אלהים
את השׁמים
ואת הארץ׃
Also in John 1, John Himself, identifies "the Word" as the eternal Person "Jesus", the very "Son" of the Father.
Joh 1:1
In the beginning was the Word, and the Word was with God, and
the Word was God.
Joh 1:2
The same was in the beginning
with God.
Joh 1:3
All things were made by him; and without him was not any thing made that was made.
Joh 1:4
In him was life; and the life was the light of men.
Joh 1:5 And the light shineth in darkness; and the darkness comprehended it not.
Joh 1:6 There was a man sent from God, whose name was John.
Joh 1:7 The same came for a witness, to bear witness of the Light, that all men through him might believe.
Joh 1:8 He was not that Light, but was sent to bear witness of that Light.
Joh 1:9 That was
the true Light, which lighteth every man that cometh into the world.
Joh 1:10 He was in the world, and
the world was made by him, and the world knew him not.
Joh 1:11
He came unto his own, and his own received him not.
Joh 1:12 But as many as received him, to them gave he power to become the sons of God, even to them that believe on his name:
Joh 1:13 Which were born, not of blood, nor of the will of the flesh, nor of the will of man, but of God.
Joh 1:14 And
the Word was made flesh, and dwelt among us, (and we beheld his glory, the glory as of
the only begotten of the Father,) full of grace and truth.
Joh 1:15 John bare witness of him, and cried, saying, This was he of whom I spake, He that cometh after me is preferred before me: for
he was before me.
Joh 1:16 And of his fulness have all we received, and grace for grace.
Joh 1:17 For the law was given by Moses, but grace and truth came by
Jesus Christ.
Joh 1:18 No man hath seen God at any time;
the only begotten Son,
which is in the bosom of the Father, he hath declared him.
And God said ... (the Father)
And God made ... (the Son, on behalf of the Father's will)
And God saw ... (the Holy Spirit, which moved and witnessed, by which we have the scriptural record, as all scripture was given by Inspiration of the Holy Ghost, and as such through holy men as they spake, being moved by the Holy Ghost, just as the Holy Ghost moved in Genesis 1)
The eternal Persons/Beings, all working in perfect harmony together, as like unto a musical "chord". The Trio.