This is a huge problem with Hindu and Buddhist religions. It is a problem with some christians, who, unless going by denominations, see christ teachings beyond scripture.
Trinity means: The creator, his son, and the holy spirit are one person in nature (they are all divine). It is in scripture.
The nature of god:
“God is a Spirit.”—John 4:24.
For since the creation of the world His invisible attributes, His eternal power and divine nature, have been clearly seen, being understood through what has been made, so that they are without excuse
Nature of christ
2 Corinthians 5:21
He made Him who knew no sin to be sin on our behalf, so that we might become the righteousness of God in Him.
Christ/Holy Spirit nature
The angel answered and said to her, "The Holy Spirit will come upon you, and the power of the Most High will overshadow you; and for that reason the holy Child shall be called the Son of God.
Nature of the Holy Spirit
because through Christ Jesus the law of the Spirit who gives life has set you free from the law of sin and death. 3
For what the law was powerless to do because it was weakened by the flesh, God did by sending his own Son in the likeness of sinful flesh to be a sin offering. And so he condemned sin in the flesh, 4
in order that the righteous requirement of the law might be fully met in us, who do not live according to the flesh but according to the Spirit. 5
Those who live according to the flesh have their minds set on what the flesh desires; but those who live in accordance with the Spirit have their minds set on what the Spirit desires. 6
The mind governed by the flesh is death, but the mind governed by the Spirit is life and peace
When you believe you are a sinner in christianity, you feel you are in need of a savior. Because that savior is an intermediary to god. In order to go to god through this intermediary, the bible (above) describes this "agent" that creates union a spirit (holy is an adjective). The Spirit (life) of go (creator) through his son (divineness of humanity) gave life to humanity (became sin), to live and teach his father's words (the Law of Moses), to die (so that christians can die), and be resurrected (so christians can be resurrected)
but this cannot happen without the creator being, well, the creator. Without the son, who is the go-between. Without the spirit-what christians receive at pentecost (in Acts as well) in order to spread Christ's Word-which is his Father's Word not his own.
That is the trinity.
What you're talking about is mainstream interpretations. Your beliefs do not define christian beliefs. You are not christian. (Or Hindu or Muslim)
So you cannot debate the internal nature of christianity unless you understand what it means to be part of the body of christ beyond symbolism.
I do not believe that jesus is god. I do understand the trinity beyond how fundamentalist describe it. I've done my research, gone to Mass, experienced it, and been devoted to it. It is not by the book. Jesus even said that "people look to scriptures as if they hold eternal life. Even they testify to my behalf." (Mark 8:24)
Stop looking at scripture to find god.