Totally untrue. Jesus said God is greater than he, knows more than he and he is going to God after God raised him from the dead. See John 20:17.
You fail to understand the Person of Jesus Christ. From all eternity Jesus Christ IS YHWH, Almighty God, absolutely EQUAL to God the Father.
The Bible teaches that there is only One God (2. Deuteronomy 6:4, etc)
That The Father is God, is not disputed by anyone.
However, the Bible also teaches that there are more than one "Person", Who is called God, distinct from the Father. In Isaiah 9:6, which is a Prophecy of Jesus Christ, it says that His Name is "’êl Gibbôr", which is "Mighty God", with the capital "G". The same Hebrew is used in 10:21; Jeremiah 32:18; etc. We know from John 1:1, that "the Word" is firstly said to be "with God", where the use of the Greek preposition, "πρός", shows that "the Word" is DISTINCT from "God". Then John goes on to say about "the Word", that He is "God" (και θεος ην ο λογος). Again, when Jesus Himself speaks of Himself and the Father, He uses the "masculine PLURAL", as in John 10:30, "εγω και ο πατηρ εν εσμεν", where the literal translation is, "I and the Father one We are". This is impossible to be taken to mean, that Jesus and the Father are One and the same Person! Paul also says in Philippians 2:5-6, that Jesus Christ existed from all eternity in the very nature of God (ος εν μορφη θεου). In this same verse Paul says, "το ειναι ισα θεω", that is, "on be on equality with God", which again must be another "Person", with Whom Jesus Christ has been "equal" from all eternity. This "equality" is what Jesus "laid aside" when He took upon Himself, "the very nature of humans" (αλλ εαυτον εκενωσεν μορφην δουλου λαβων), with the exception of sin.
Hebrews 2:9 tells us that Jesus became "lower" even than the angels, because of His suffering and death.
"But we behold Him who hath been made a little lower than the angels, [even] Jesus, because of the suffering of death crowned with glory and honor, that by the grace of God he should taste of death for every [man]"
The words "a little lower", means, "for a little while”, showing that it was only during His Incranation.
Jesus Himself says that He was The Servant, as Mark 10:45 says, "For even the Son of Man did not come to be served, but to serve, and to give His life a ransom for many.”. He also said that the "A servant is not greater than his master." (John 15:20). God the Father during Jesus' Incarnation, was "the Master", and Jesus Christ was His "Servant". Hence the subordinate role. However, even during this time, Jesus could demand that ALL people were to "Honor" Him, in exactly the same way they "Honored" The Father. And, those who did not "Honor" Him, did not "Honor", the Father,m Who sent Him. (John 5:23). Not only is this very clear personal testimony from Jersus Christ on His own Deity and equality with the Father; But, the fact that He says that the Father "sent" Him, where the verb "πέμπω", is used for one person sending another. Which clearly shows DISTINCTION between Jesus and His Father!
It is also very clear from passages like John 17:5, that this "subordination" of Jesus to the Father, was functional, during His earthly life. As Jesus says that He shared the SAME "Glory" with the Father from all eternity, and after His Ascension, was returning to this state.
"And now, Father, glorify thou me with thine own self with the glory which I had with thee before the world was"