According to the Mormons, Jesus is a separate being, but one in PURPOSE with God the Heavenly Father. They believe God has a body of flesh and bone, and that God was once a man who has progressed to become exalted and now he is a God. In other words, for Mormons, God, as an exalted man, was not always God. According to them, once upon a time God was an ordinary human.
They believe that Jesus is the “Jehovah” of the Old Testament and the creator of this world. They believe there are other worlds besides ours. I have never heard anything definative about who is in charge of those other worlds. They believe that, like God, we humans can also progress and become exalted and become Gods of our own worlds.
They believe that the Holy Spirit is yet another separate being, also one in PURPOSE with God the Heavenly Father and Jesus. But they also call God, Jesus, and the Holy Spirit, taken together, to form their version of a “Trinity”. They will at times, although it is rare, even use that word, but their understanding of the “Trinity” bears no resemblance to the beliefs of most other Christians.
I suppose that these doctrinal differences are the main reason that many other Christians do not consider Mormons to be Christian. At the very least, because the differences are so very extreme, even if other faiths call Mormons “Christian” it is only on a very qualified basis.
I suppose that is a round about way of answering your question and I am sorry if that was too much, but it is hard to answer without some background. In the Mormon hierarchy, it would appear to me that God is superior, but that is more of a conclusion of my own, based on everything else, I do not remember ever hearing it defined as such. I do not know if they think of God as #1 and Jesus as subordinate, but they definitely believe that Jesus is a separate being.
Because Mormons use the same terminology, it is easy for unsuspecting people to be mislead into believing that Mormons believe these words mean the same thing as other Christians do. That would be a mistake.