Jesus is God
Holy Spirit is God
Father is God
God is Trinity.
Jesus tells his apostles to baptize "in the name [notice, singular, not plural] of the Father and of the Son and of the Holy Spirit" (Matt. 28:19). This is a proof-text: three distinct Persons united in the one divine name. In 2 Corinthians 13:14, Paul writes, "The grace of the Lord Jesus Christ and the love of God and the fellowship of the Holy Spirit be with you all." We see this same unity of divine Persons in 1 Corinthians 12:4–11, Ephesians 4:4–6, and 1 Peter 1:2–3.
The Bible clearly teaches that Jesus is God (cf. John 8:58, 10:38, 14:10; Col. 2:9). It also clearly teaches that the Holy Spirit is God (cf. Acts 5:3–4, 28:25–28; 1 Cor. 2:10–13). Everyone agrees the Father is God. Yet there is only one God (Mark 12:29, 1 Cor. 8:4–6, Jas. 2:19). How can we hold all four truths except to say all three are One God?
And yes, Jesus DID say he was God. In John 8:58, when quizzed about how he has special knowledge of Abraham, Jesus replies, "Truly, truly, I say to you, before Abraham was, I Am"—invoking and applying to himself the personal name of God—"I Am" (Ex. 3:14). His audience understood exactly what he was claiming about himself. "So they took up stones to throw at him; but Jesus hid himself, and went out of the temple" (John 8:59).
Also significant are passages that apply the title "the First and the Last" to Jesus. This is one of the Old Testament titles of Yahweh: "Thus says Yahweh, the King of Israel and his Redeemer, Yahweh of armies: ‘I am the First and I am the Last; besides me there is no god’" (Is. 44:6; cf. 41:4, 48:12).
The hypostatic union makes no sense
That is your problem. It makes sense to the entire Christian Church though.
Jesus is fully God and fully man. He has two natures perfectly united in one person. The term used to describe this is the "hypostatic union".
The hypostatic union is the term used to describe how God the Son, Jesus Christ, took on a human nature, yet remained fully God at the same time. Jesus always had been God (John 8:58, 10:30), but at the incarnation Jesus became a human being (John 1:14). The addition of the human nature to the divine nature is Jesus, the God-man. This is the hypostatic union, Jesus Christ, one Person, fully God and fully man.
Jesus' two natures, human and divine, are inseparable. Jesus will forever be the God-man, fully God and fully human, two distinct natures in one Person. Jesus' humanity and divinity are not mixed, but are united without loss of separate identity. Jesus sometimes operated with the limitations of humanity (John 4:6, 19:28) and other times in the power of His deity (John 11:43; Matthew 14:18-21). In both, Jesus' actions were from His one Person. Jesus had two natures, but only one personality.
So the Father, Son and Holy Spirit are distinguishable from one another in terms of hypostasis (the Scriptural term used, for example, in Hebrews, where Christ is the exact image of the hypostasis of the Father), but they are not "separate" (apart from one another or by themselves), as they share the same nature and same energy, but furthermore, as they are limitless, there is a perichoresis or "interpenetration" of the persons.
So there is similarity, but the similarity ends with the fact that the Divine nature is infinite and incorporeal, and human nature is finite and corporeal (as with all of created nature).
Hebrews: "God, who at various times and in various ways spoke in time past to the fathers by the prophets, has in these last days spoken to us by His Son, whom He has appointed heir of all things, through whom also He made the worlds; who being the brightness of His glory
and the express image of His person, and upholding all things by the word of His power (ὃς ὢν ἀπαύγασμα τῆς δόξης καὶ
χαρακτὴρ τῆς ὑποστάσεως αὐτοῦ, φέρων τε τὰ πάντα τῷ ῥήματι τῆς δυνάμεως αὐτοῦ)