Atheists don’t believe in god. We don’t pretend to have all the answers. Just because you lack knowledge, doesn’t mean “god did it “.

Once again, this isn't the province of "atheism", rather, it's the province of cosmological physics. Which you would know if you didn't have this strange obsession with ascribing to atheism topics that are not part of its remit.

Once and for all, learn this elementary concept. Atheism, in its rigorous formulation, is nothing more than suspicion of unsupported supernaturalist assertions. That is IT. Atheism doesn't involve presenting assertions of any sort on any topic, and leaves this process to [1] supernaturalists like you, or [2] whichever requisite experts in the requisite disciplines can both present relevant assertions, and the supporting evidence for those assertions. Learn this elementary concept quickly to spare yourself even more embarrassment than you've already acquired here.

Now, as to the matter of the ideas arising from cosmological physics, there are a number of these, and any reasonably diligent perusal of arXiv will find plenty of papers discussing these ideas, and the attempts to formulate those ideas in a rigorous manner. However, proper understanding of many of these papers requires a grounding in tensor analysis, and in particular, the rather intimidating mathematics of the Ricci calculus, which is the branch of mathematics specifically formulated to deal with such topics as curved spacetime geometries, spacetimes with many dimensions, and the multifarious offshoots of String Theory. However, the foundational concepts contained in some of those papers can be presented in elementary terms, because the authors thoughtfully provided the requisite expositions.

One example exposition I am aware of, arises from two papers written by Paul Steinhardt and Neil Turok. Fortunately I don't have to recapitulate the entire exposition on those papers, because I provided a post here back on March 24th, 2019, that contains said exposition, and you can click on that link and peruse the details at leisure.

However, the important point to realise at this juncture, is that there is one feature that all of the various hypotheses presented in the world of cosmological physics have in common, namely, that they postulate the existence of testable natural processes that are responsible for the instantiation of the observable universe and its contents, along with relevant well-defined entities and interactions. Though in the case of those entities and interactions requiring definitions via the Ricci calculus, untangling what these are precisely is itself a major undertaking for non-experts in the field. However, the papers in question are intended to be read and understood by other trained cosmological physicists, so the terseness of some of those papers is unsurprising in the light of this fact.

In the meantime, I suggest you familiarise yourself not only with the elementary concepts I provided above, but the relevant hypotheses and their accompanying papers.

AJ777: How can atheism account for the existence of the universe? Or, on the atheistic view, where did the universe come from?

Your questions assume the universe was created.

AJ777 - How can atheism account for the existence of the universe?

Dude, I can't even account for my socks.