You just misunderstood the verses u cited.

This was an instance wherein God the Father, Jesus and Holy Spirit were present at once. This will surely disprove the trinity 😅

Mat 3:16-17 KJV

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:
17 And lo a voice from heaven, saying, This is my beloved Son, in whom I am well pleased.