Those questions about color range are from the video guide and I’ll admit they’re a little weird.
Can RGB values be any other range besides 0-255?
You could answer two ways:
No. On modern computers RGB values are expressed as one byte per color channel (0-255). End of story.
Sure, the could be another range as long as computers supported it. You could assign an arbitrary number of bits to each color channel. As long as the protocol/format is well defined then the image could be rendered. (There is probably a physical limit to how many gradations of light intensity can be produced in hardware. So if you went nuts and said each color channel could have 32-bit settings (~4 billion values) it might not be physically possible to make a screen do that.
This ^^^ is sort of an answer to what happens if you increase the range too. But the answer shown above is what I would expect. There are two things to consider though. 1) yes, you can increase the number of colors you can represent, but 2) you also dramatically increase the file size. Consider: every bit you add to the definition of each color channel adds 3 bits to the definition of each pixel. So for, say, an 800x600 image (small by today’s standards) every bit you add to the color channel definition results in an increase of (800 x 600 x 3) bits == 180 kilobytes. So that’s a consequence as well.