Your question is about the hard problem of consciousness, which is basically the question of how qualia can be explained in a mechanistic way. As alluded to by the name of the problem, it's hard to give a satisfactory answer. The answer right now is: we don't know.
There are some theories about how qualia and consciousness could have a neural basis (see this questionthis question and this wikipedia article). But none of these theories are widely accepted by cognitive scientists and there is still considerable debate over the issue.
Your question also illustrates another philosophical issue in the philosophy of mind. You asked:
So why does the human brain take the extra steps of combining both signals into an image - i.e translating the different waves of the electromagnetic spectrum into shapes, colors, etc -, turning it upright and displaying it to ourselves
The idea that conscioussness and qualia reconstruct the world and then we act and perceive on that world creates a problem: how do we act an perceive on that world? Do we reconstruct it? If so, then we are back to the original problem. This is called the homunculus argument, and it illustrates the fact that we haven't explained anything if we posit that the purpose of qualia is to reconstruct what's already out there.