The Trinity is altogether another can of worms, and is often misunderstood. The teaching occupied the theological aspirations, and intellectual capabilities of the early Christian Church for over three centuries [which is a lot more than 5 minutes] before the issue was established.
It is often said that the Trinity teaching is not in the Bible, which is true. However, the Teaching of God is found fully articulated in those very same pages, and that has formed the basis of the Christian teaching of who the Father, Son and Holy Spirit are. The teaching of the Trinity whether you agree with it or not, is simply not that "Jesus is God" and that's it. It is far more complex and circumscribes 6 main specifics:
1. The Father is God. [there is no "Jehovah" in the NT, and the early Christians, even in the first century, always appealed to this Personage as the "Father" and never "Jehovah". The earliest records we have such as "The First Letter of Clement" written sometime before the writings of John, speaks of how "we love the Father". Introducing the "name" Jehovah here muddies the waters and blurs the relation between the Father and Son]
2.The Son is God. The very same word used of the Father is used of the Son in the NT. To say that the word "God" [Greek Θεος] when used of the Father means "God" but when used of the Son simply means "a god" is not acceptable by True Christians whether from the first century of the twenty first.
3. The Son is also a Human Being. The same Gospel writer who calls Him God [John] also calls him Man. If one expression is literal so must the other. We are not required to understand it, or to modify it so as to conform to something called "human reasoning" but simply to accept it.
4. The NT also indicates that the Holy Spirit is God
5. Yet there is also only One God.The early Christians never abandoned their belief in Monotheism.Thus, in some way that passes all human understanding, the God of the Bible is portrayed as far more complex than a simple Monadic view [One Person in One God] would suggest.
6. Within the Trinity there is a titular distinction. The Son, although fully God, is nevertheless Subordinate to the Father. And the Holy Spirit is Subordinate to both the Father and the Son, despite being fully God.
Now, to answer some of your questions:
A. Jesus was able to pray to the Father because He was a Man who needed the spiritual proximity of God, as should we all.
B. Jesus is God, but He is not the Father. Don't blur the distinction in these words.
C.Trinitarians are specific in their vocabulary since the NT itself is. Thus we say that the Father, Son and Holy Spirit are Distinct but not Separate. You cannot separate the three, because the Father is 100% God, the Son is 100% God, and the Holy Spirit is 100% God, Distinct but not Separate.
When you combine all the specifics in the Trinity it should answer such questions as:
How can Jesus be God if He was tempted, since God cannot be tempted, How can Jesus be God if He did not even know when He was coming again, How can Jesus be God if.......etc etc.