The Holy Ghost is the Spirit of God as He is released back to the Father (Luke 23:46).
To get the rest, I suppose that you will have to seek to understand the relationship between time and eternity.
You should have studied-out "omnipresent".
Omnipresence has Jesus coming out of the water at the baptism of John, and simultaneously descending like a dove (which was a sign unto John), while speaking from heaven in
Matthew 3:16, which was a perfect example of how our one true God can multitask. God does not jump out of one person in Mexico to go and jump into another saved person in France, He is in all saved people
at the same time, and was in all three places at that baptism while still being the
one omnipresent Spirit which is in heaven...
Matthew 3:16 And Jesus, when he was baptized, went up straightway out of the water: and, lo, the heavens were opened unto him, and he saw the Spirit of God descending like a dove, and lighting upon him:
Luke 3:22 And the Holy Ghost descended in a bodily shape like a dove upon him, and a voice came from heaven, which said, Thou art my beloved Son; in thee I am well pleased.
That same God which spoke to Moses through a burning bush, overshadowed Mary and she conceived a seed. That one spirit simultaneously inhabits that seed AND remains in heaven (omnipresent). When Mary gives birth, we now have SPIRIT become FLESH. That bouncing baby boy is the ALMIGHTY manifest in the flesh. That is how, and why Jesus can say, "the Father that dwelleth in me, he doeth the works." ... and ... "he that hath seen me hath seen the Father."
Compare the following references:
The Lord God is the Creator.
Isaiah 42:5.
The Lord Jesus is the Creator.
John 1:3-10.
The Lord God said, "I am He."
Isaiah 43:10.
The Lord Jesus said, "I am He."
John 8:24.
The Lord God is the only Saviour.
Isaiah 43:10-11.
The Lord Jesus is the Saviour.
Titus 1:4.
The Lord God shall reign forever.
Psalms 146:10.
The Lord Jesus reign forever. Luke 1:33
The Lord God is the King of Israel.
Isaiah 43:15.
The Lord Jesus is the King of Israel. Matthew 27:37
The Lord God is the First and the Last.
Isaiah 44:6.
The Lord Jesus is the First and the Last.
Revelation 1:8.
Is it possible Jesus is both the Father and the Son? Jesus himself addressed this very question...
Luke 20:41 And he said unto them, How say they that Christ is David's son? [42] And David himself saith in the book of Psalms, The LORD said unto my Lord, Sit thou on my right hand, [43] Till I make thine enemies thy footstool. [44] David therefore calleth him Lord, how is he then his son?
Revelation 22:16 I Jesus have sent mine angel to testify unto you these things in the churches. I am the root
and the offspring of David, and the bright and morning star.
Jesus is the First and the Last.
He is the Alpha and the Omega.
When talking with the Jews, he said...
John 8:24 I said therefore unto you, that ye shall die in your sins: for if ye believe not that
I am he, ye shall die in your sins.
[27] They understood not that he spake to them of the Father.