Here I hope by God's grace to answer 4 questions given to me on a video called "Pros and Cons of Messianic Judaism": https://www.youtube.com/watch?v=w7ww6OLzFE8
"1. In the doctrine of the Trinity, are the Father, Son, and Holy Spirit three separate, independent "persons" capable of knowing, saying, and doing things apart from the others?"
They are distinct persons, but they do not act independently from one another. The Son only does what the Father commands and the Spirit only does what is commanded of the Father and the Son. They do not act independently from one another but act in unity and purpose with one another.
"2. Is each one considered a god separate of the others?"
A distinct person yes, another God, no. One being in three persons. Being is what you are, Person is who you are.
"3. If they are all gods, please explain the events in Mt. 3:13-17. If each of them is God, that's three gods at one baptism; and, what did Jesus need with the "Spirit of God" if he was a god."
No, one God in three persons.
Furthermore, you comment shows some ignorance on the Trinity itself.
Jesus (see Philippians 2:5-11) took on himself a human nature. He didn't cease being God, but laid aside his divine prerogatives and depended on the Spirit for source and sustenance. It was also a demonstration to Christians to be dependent on the Spirit which in turn would help us to obey the Father (And in turn also obeying Jesus). See James White's comments in his debate with Jalal Abularub from 3:51-4:27: https://www.youtube.com/watch?v=2yTlx943q28
"4. Why call yourself a Trinitarian if you don't mean that each is a god? Everyone already accepts the existence of the three, so why even bring it up, and, why have so many people been murdered over the issue if it was all just semantics? You deceive yourself, not me."
The term Trinitarian refers to the person who believes in the Trinity ie. One God in three persons. What is your question even about? I wasn't saying the Unitarians deny the existence of the three, that wasn't my point to begin with. People have died for theology on both sides or killed on both sides, Why is that even brought up as an objection?