Whether or not the Universe requires outside intervention to come into being.
Whether or not something can come from nothing.
Whether the matter or energy that expanded into our current universe may have existed in one form or another forever.
Lets start with the first question.
1).In the distant past everything we did not know about, we attributed to some divine creatures (gods). First divine creatures looked like us, but as we later learning about the enormous scale of energy/force required to drive most events around us, then we re-named them "divine powers", or "supreme beings").
So, in the distant past we believed that plants or animals come from gods in grown-up appearance and were around forever since. We called it "creation" of plants, animals, etc. Then upon close observation we found that plants actually come from seeds. Now, the question: is a plant created by god(s)or does it EVOLVE from a seed in accordance to natural physical laws? Is the seed created by God or does it evolve in the parent fruit in accordance to physical (mathematical) laws?
And so on. And this EVOLUTION (or dynamics) of physical processes is in each and every phenomena of birth where you try to find "divine creation". Where did all universe come from? Creator? "Yes" -was an answer just a few hundred years ago. "Nope" - is today's answer "-It evolves from Big Bang". Where does Big Bang come? It looks like it evilves from inflation, and inflation seems to evolve from false vacuum. So, each and every effect, every phenomenon (including universe itself) is a mathematical result of more deep phenomena/processes when you try to dig into its cause. It was ALWAYS in the past and present that the cause was mathematical too and came from something mathematical too. So, there is no reason to believe that there is a creature which makes a tree out of a seed, or makes a Big Bang out of inflation.
Now, about somebody divine flying among false vacuum and pushing big red button with the sign "Inflation start". If there is some event triggering inflation and burth of universe, it is highly likely physical (=mathematical) event - because it was always was in the past that everything had its physical cause. But physics (math) does NOT prohibit spontaneous events - as long as they do not violate mathematical rules. Say, particles can pop out of vacuum and disappear back (but not without trace - all known forces ARE the result of interaction of these virtual particles with "ordinary" matter). So, spontangeous events CAN happen without any divine help. And inflation could also take place spontaneousely.
2). Can something come from nothing? Mathematics does not prohibit that: 0=-1+1. So, you can have a chunk of positive energy (matter) and a negative (gravity) out of nothing, as long as total energy is zero. Or you can have opposite charges to appear out of neutral state of matter. So, creation of something out of nothing is not prohibited and thus does not require Creator input too.
3). It seems that the balance of energy in our universe is zero (gravity balances matter), so it does not require any matter/energy to be used to create it. But even if it is not zero, then this energy was just in different form prior to birth of our universe, and the birth is just a change of the state of this energy.