If you're more interested in consciousness a good place to start is "Conscious: A Brief Guide to the Fundamental Mystery of the Mind" by Annaka Harris.
That sounds like a recommendation to me!
On the biology part, if you never have heard of terms like "efference copy" it will be interesting food for thought about what consciousness might be, but no "solution" really. And you'll learn that an octopus is a ten megapixel screen, but that's just the first point again. If you only want that first point, there is also a "My Octopus Teacher" on Netflix, which is great in its own way.
If you wanted to read about human intelligence, I suggest "The Secret of Our Success" by Henrich instead.
Can you expand on this? I think I kind of understand where you're going with this: consciousness might be an efference copy of our actions? (so our actions don't "surprise" us? rather than consciousness creating actions?)
First it's just a nerve-path to prevent flinching back from the contact with something you wanted to manipulate. But once you have a fancy neural path that tells the visual cortex what light/objects to expect after you move your head left/right (maybe flee if it's unexpected), it's only a small evolutionary step to re-purpose this path, "execute" the same path while suppressing the head movement. So now you can process further what you are expecting if you move left vs right. Which could be interpreted as a step towards being conscious of your surroundings. (This is not 100% what the book says, but the idea I got from that chapter.)
He spends very little time drawing connections to consciousness or speaking about what octopus life can tell us about consciousness. There is a whole chapter where he talks about the influence of language in human action (like self-talk), and then ends the chapter by with something like "and octopuses don't have this ability". What was the point of that whole chapter then?
Maybe my expectations were miscalibrated, and I thought he would spend more time drawing connections between octopuses and humans, and what those similarities could tell us about consciousness. Instead of that, the writing about consciousness in this book is quite shallow.