Not even atheists believe that the universe came from nothing, but the quantum fields and eternal inflation they postulate must have existed in order to produce such a universe are no less incredible.
But the real difficult problem that atheists and agnostics struggle to account for is something called the "fine-tuning of observability". Suppose there are an infinite number of universes produced in sequence- most of them dead- but a select few with the perfect fundamental constants exist somewhere, and those eventually beget life. By the anthropic principle it is unsurprising that we find ourselves in a universe that supports complex life, no matter how rare or unlikely the odds.
The problem is that the overwhelming majority of these life-supporting universes only barely do (with relatively high entropy), but we find ourselves in a much-better-than-typical universe in which it is even possible to discern that the universe had a beginning. See [1], [2], and [3]. Now, an intentional creator God would be interested in the universe being observable, so that his divine nature could be seen from the things that were made [4]. No natural explanation remains for why our universe is exceedingly low-entropy and highly-observable except that it was intentional.
[1]:
https://arxiv.org/pdf/hep-th/0208013.pdf (Disturbing Implications of a Cosmological Constant), Dyson, Stanford University
[2]:
https://arxiv.org/pdf/1606.08448.pdf (Relative Likelihood for Life as a Function of Cosmic Time), Loeb, Harvard University
[3]:
https://arxiv.org/pdf/0704.0221.pdf (The Return of a Static Universe and the End of Cosmology), Krauss, Case Western Reserve University
[4]: Romans 1:20 (CSB): For his invisible attributes, that is, his eternal power and divine nature, have been clearly seen since the creation of the world, being understood through what he has made. As a result, people are without excuse.
The above outlines the background and reasonableness of theism but it does not say anything about Christianity being true compared to any other religion. The veracity of Christianity depends entirely on the truth of the physical resurrection of Jesus circa AD 33. The stories of the resurrection were not oral tradition passed down for generations before finally being recorded centuries later. Mark was written in the AD 60's- a fact not even disputed by secular biblical scholars.
The issue that agnostics and detractors struggle with here is this: There hasn't been any successful alternative theory as to how this group of defeated apostles radically changed and took their conviction to their grave even under persecution. There have been many attempts (stolen body, swoon theory, conspiracy theory, etc) but they do not hold up under scrutiny. Liars make terrible martyrs. (and even the concept of a resurrected messiah was utterly foreign to first-century Jews). [5]
[5]: A fun illustration:
https://www.youtube.com/watch?v=23UNLLbOS3w
Ultimately, sure- some things may have been lost or altered in translation/transmission, and Jesus was probably not born on Dec 25. But these end up just being nit-picks- a distraction, and nothing more, and they're not significant enough to change the conclusions above.
So, how do I deal with athiests or satanists who don't want to understand / disrespect / etc? You just give the best evidence you can and that's good enough. Rejection is not something to be scared of- it's sometimes just part of the process[6]. If something is true, disbelieving it doesn't make it disappear. I cannot imagine standing before the throne of God with a defense of "I ignored everything, and so I didn't know."
[6]: See the entirety of Mark 5 for examples of this.