When I was a young man, I became deeply fascinated with black holes. I'd lie in my bed at night and try to imagine what it would feel like to enter one.
Because we're basically looking at it from the "top" of the accretion disk. That's not exactly correct, but the way light and gravity mix the image isn't perfectly uniform.
The brightest edge of the picture is the matter heading toward us, where as the darker edge it's heading away.
The image you shared has a bit of artistic touch. It's hard to visualize how a disk of matter spinning in one plane can emit light in the massively warped space around a black hole.
Because we're basically looking at it from the "top" of the accretion disk.
I'm not sure which way M87 points, but for Saggitarius A*, shouldn't we be seeing it pretty much edge on? Our solar system is in the plane of the Milky Way.
it's too tiny to take a picture of using a traditional telescope, so instead, they use multiple telescopes around the Earth, and piecemeal that data together. Which means they have to reconstruct the missing details (it's not made up, it's more like playing "connect the dots" with tons of math)
The resulting black and white images are given different colors, then blended together (which is pretty similar to how cameras take images, they just map the grayscale images to colors we can see with our eyes)