So, where do we start? How do we start? This might be the most difficult part. Depending on what history you have been taught, what morals you have been taught, the picture in your head of the world and people can look completely alien to another. At a more fundamental level, if each and every one of us has truly unique experiences (no one else can see through your eyeballs at any given time!), how can we possibly structure an understanding of the collective history of humanity without bias?
We cannot remove bias, as much as we may want to to conduct a "scientific" analysis. To study humans means to study our biases themselves! At the risk of sounding paradoxical, a scientific analysis done by humans on humanity, cannot be literal, experimental science. Now, that is not to put disrespect on experts in the social sciences; I very much regard these fields as scientific, nor do I intend to do a "non-scientific" analysis! What I mean by this is that unlike a chemistry or physics experiment, we cannot create a controlled lab setting or repeatably measure with absolute mathematical precision the collective actions of humans, especially when analyzing history. What we can do is analyze patterns and discover general tendencies of human history, which is often understood through science-like (dialectical) methods of logic and reasoning. This isn't to mean that these tendencies we learn about humanity is vague or not based on the physical laws of the universe. We approach hard science in quite a similar way. What is "temperature"? Is it not the measurement of the average kinetic (moving) energy of a collection of particles in a system? Of course, not a perfect analogy, but I hope the point is coming across. Each individual particle may be moving relatively faster or slower than those around it, but through physical interactions (analogous to the social relations of production, perhaps?), an overall tendency of the system can be observed. Anyways, what I mean by this is that the very observation of humanity by humans affects humanity itself, unlike conducting experiments on inanimate objects (quantum mechanics might throw the analogy off, I am thinking more of classical physics).
So when we study human history, and especially the history and mechanics of capitalism, we cannot approach it like we are removed from it, probing it in a controlled lab setting. So the same kind of experimental approach of a physicist cannot apply cleanly; we must work with the fact that we are looking at a dynamic system that responds to the very act of its own criticisms. There are plenty of sources for heterodox analyses of capitalism, I won't be replicating them in length here. I will share what and where I have learned, and why I think the Marxist approach to analyzing the course of humanity is a much more well-rounded, fuller picture of "everything."
And lastly, as much as I struggle with this myself, we've gotta do the readings. Audiobooks are good too, but sitting down and slowly reading difficult texts, ideally with notes, is and has been the way to distill dense data. This site isn't intended to replace actual texts, only at best to be a rough guide/journal to know where to even look. Always read the texts and use them as your sources of information!