@FBM,
I like your approach as it involves not just making statements as a rebuttal but also asking questions which stimulate thinking.
Lets deal with question 1: The beginning of our universe is known to have sprung from one massive event (big bang). Scientists are still interested in finding out what made up this event. And what precipitated its expansion into what we now call the universe. The current consensus is that the element(s) involved in the creation of our galaxy did not always exist. Thus raises the question. Where did it come from?
Question 2 answer: A key to answering this question is to intertain the possibility of there existing a being that to which the laws of physics do not apply. These laws being made for the benefit of those things that would need them. Thus this creator would exist above and beyond the laws that govern all matter. A Bible text that conveys this thought is 1Ti 1:17 which states: "Now to the
King of eternity, incorruptible, invisible, the only God, be honor and glory forever and ever. Amen."
Question 3 answer: This is pretty much covered by the answer to question 2. Being that Jehovah God is not affected by the laws he created. Then the thought of his having had a beginning would not apply.