1) Point taken, this needs a lot do research but I want a clarification from you. You do believe something can come out of nothing?
3) I wasn't raised to be religious, my family is very moderate and unlike me. I later during my high school period had lots of free time and tried discovering religion but also the scientific aspect of life so I can relate to both. I see it's not an insult, but could I move to my next question? And does me being somewhat religious make my question any more or less credible? I'm a young adult.
1) Oh, that's not just my belief, that's demontrated both theoretically as well as experimentally:
Are virtual particles really constantly popping in and out of existence? Or are they merely a mathematical bookkeeping device for quantum mechanics? - Scientific American
Something from Nothing? A Vacuum Can Yield Flashes of Light - Scientific American
Can You Get Something For Nothing? – Starts With A Bang
Yes, things can come out of nothing. By the way, remember that most people have never seen a "nothing" in their lives - real nothing is very, very rare. You are surrounded by matter and/or radiation everywhere. But yes, particles can and do arise from pure nothing all the time. The proof would be way beyond the scope of this website, but there are resources out there.
3) No, it does not make your questions any more or less credible. As I said, I only mentioned it because all of us - you, me and pretty much everybody on earth have been conditioned to approach the question from a religious or quasi-religious POV. The very fact that everybody asks "why" instead of "how" shows that everybody is assuming intent, that a mind (god) intentionally did some things. "Why" is about intent, "how" is about a mechanism. Not everything is intentional, and therefore not everything has an answer to "why".
And I know you are a young adult, for most people that's the only time they ponder these questions. Unfortunately.
So you're saying the Universe always existed and just expanded itself? So why are you coming to an conclusion that nothing preceded it or it wasn't created(Or came into existence if that's what you like to call it) if we just don't know(as of yet).
If we don't know anything through science, that's definitely a possible assumption, is it not? Maybe it existed all the time? After all, that's the answers that religions provide - everything was created by a god/allah/brahma, and that god/allah/brahma always existed. Well that's a non-answer, a non-explanation. In that case why assume the need for a god, simply state that the universe always existed. Why add that additional step? That's just shifting the mystery from how the universe came into existence, to how a god came into existence, and then saying the god always existed. A much better explanation is simply that the universe always existed.
But that's just the answer to the plausibility - as to what really happened, that can only be known through science. As of now, scientists only know what happened during and after the big bang. What happened in the first few moments, we cannot know as of now, because we don't know the required math or physics. Maybe we will never know. But in such cases, it is always better to say we don't know, than to offer non-answers.