I will answer your from the last to the first:
The answer is in His name, 'Jehovah', which literally means the self existent one.
I did 10 minutes worth of study on the meaning of the name 'Jehovah' and come up with for meanings:
You alone are the most High
Eternal one, self existent
He brings the host into existence
He brings into existence anything that exists
So as everything in religion, there are many meaning for the name Jehovah, which one is the real name? Just try to give me any details on what 'Self Existent' means. You can use words like "he stand outside of time and space", and he is 'uncreated', but all of that does not get to the bottom of "how" He is. Like I say, try to find the words 'self existent' in the bible. You won't.
If God does not determine His own nature, then He must be created.
And if one is created, does that exclude that person from becoming an 'all powerful' being in millions of earth years? We already know that our vile created mortal bodies will be changed into a resurrected, incoruptible, immortal (will live forever and never give out again) body, just like the body of the Lord Jesus. So what is so degrading about having been created. Cannot the Creator give to the created everything that He has, even His divinity? Is our all powerful Creator not powerful enough to endow his creation with divinity? What scholar came up with the idea that since we are created, we can not be divine? This idea means there are limits to God's power. I agree with you that God is "all powerful".
Yes, there are two, but remember, tho Christ has the same nature as His Father, He does not occupy the same position as God to God, for there can only be one true God, and He is the God of Christ.
Yes, there are 2, and Jesus cannot occupy the same position as God the Father, nor can Jesus occupy the same space in time as God the Father. They are 2 distinct and separate Individuals with one purpose and one goal, to bring about the Eternal life of mortal men. Do you understand what Eternal Life means? It means the same kind of life that God lives.
Fellows means brothers--He is, after all, the firstbegotten, a term which denotes that God will beget more.
Interesting scripture, Psalms 45:6-7 is an interesting passage. When did that conversation take place? Before the earth was finished. Where did that conversation take place? In heaven. Who was the conversation between? 2 Gods, God the Father, talking to his Son, God the Son.
Conclusion: The Sons 'fellows' alrady existed in heaven before the earth was completed. Interesting don't you think?
To ask "how God became the Origin" presuppose that at one point He was not, which assumes the truthfulness of the basis of your argument, which is literally, the very thing I am arguing against. --I hope you can see, that that is not the "bigger question" but that it is merely begging the question.
Yes, I can see your point. If God 'became', he didn't exist before he 'became'. So I will go a different direction. How did God become all powerful?
It is unnecessary to consider all other God's before God: to conclude that He is not the origin only requires just one God before Him...
It is unnecessary to consider all other God's before God: Therefore we conclude that He is the origin of our heaven and our earth as stated in Genesis 1:1, and all things within that heaven and earth.
He is of a long line of holy Gods, that make up the word God. God is the origin of everything in the universe and beyond our knowledge of things.
God's nature cannot be fully understood by us now, but what is easy to understand is what He has revealed about Himself, through His Son, that He is one, and that He begat a Son, and that we must obey His Son.
You are right. God's full nature cannot be fully understood by us now. Jesus has revealed at least part of His nature. Since Jesus is an exact image of his Father, his Father must look just like him. This much we do know, which is an important incite into the nature of God the Father. When we meet them, we will be given all the secrets and it will be an interesting day to sit at their feet and here the full truth.