In John 17:5, just 2 verses after 3, Jesus says
“Καὶ νῦν δόξασόν με σύ πάτερ παρὰ σεαυτῷ τῇ δόξῃ ᾗ εἴχον πρὸ τοῦ τὸν κόσμον εἴναι παρὰ σοί”
“And now Glorify Me You Father with Yourself with the Glory that I had before the world existed together with You” (literal translation)
ONLY if Jesus Christ is COEQUAL with the Father, could He have said these words!
He is saying to the Father, that His Glory is the SAME as His, and this Glory has COEXISTED with the Father, from all Eternity!
In Isaiah 42:8 it says, “I am YHWH, that is My Name; I will not give My Glory to another or My Praise to idols”.
Note the words, "I will not give My Glory to another". And yet Jesus Christ says that His Glory is exactly the SAME as the Glory of the Father!
In Revelation 5:13-14 we read
"And ALL of the Creation, which is in the heaven, and on the earth, and under the earth, and on the sea, and all things that are in them, heard I saying, to Him Who sits on the throne, and unto the Lamb, be ALL the Blessing, and ALL the Honour, and ALL the Glory, and ALL the Might, for ever and ever. And the four living creatures said, Amen. And the elders fell down and Worshipped." (so emphasized in the Greek)
Also note here, "AND TO THE LAMB", which is the Lord Jesus Christ.
ALL The Blessings, ALL The Honour, ALL The Glory, and ALL The Might, that is to be given by ALL Creation, to The Father, is ALSO to be given EQUALLY to Jesus Christ! And then they are BOTH WORSHIPED TOGETHER! There is NO distinction made!
On Hebrews 1:8, in its context, we read in verse 6,
“But when He again brings the Firstborn into the world, He says: “Let all the angels of God Worship Him”
We here have the Greek verb “προσκυνησάτωσαν”, which is in the imperative mood, which is an Authoritative Command, given by the Father, to WORSHIP Jesus Christ.
The Father would not say this, IF Jesus Christ is not 100% COEQUAL with Him as YHWH!
In verses 10-12, the Father continues to Address Jesus Christ;
“And: In the beginning, Lord, You established the earth, and the heavens are the works of Your hands; they will perish, but You remain. They will all wear out like clothing; You will roll them up like a cloak, and they will be changed like a robe. But You are the same, and Your years will never end” (Hebrews 1:10-12)
This passage is continued from verse 5, where the Father begins to Address Jesus Christ:
“For to which of the angels did He say at any time, “You are my Son. Today I have become your Father?” and again, “I will be to Him a Father, and He will be to Me a Son?””
In verse 10, “Lord” is the Greek “Kurie”, which is in the vocative case, used in direct address, which here is by God the Father, to Jesus Christ.
The words in verses 10-12, are from Psalm 102, where it is used for Almighty God:
“I say: “My God (’êl), do not take me in the middle of my life! Your years continue through all generations. Long ago You established the earth, and the heavens are the work of Your hands. They will perish, but You will endure; all of them will wear out like clothing. You will change them like a garment, and they will pass away. But You are the same, and Your years will never end.” (verses 24-27)
The fact that God the Father here clearly Addresses Jesus Christ, as THE CREATOR of the entire universe, is the strongest Testimony that Jesus Christ is Almighty God. The passage in Psalm 102, is of Creation by Almighty God, and it is directly used for Jesus Christ in Hebrews, by God the Father.
No doubt whatsoever that Jesus Christ IS Almighty God, as Testified by God the Father Himself!