Pantone is not a color space. They are a supplier of physical color samples. Most pigments can be represented in a color space, but that representation differs based on illumination so it not unique. Some Pantone pigments, fluorescent colors in particular, cannot be represented by a color space at all!

Yup. This is a rabbit hole like time. Learn a little bit about it, know there's a staggering amount more and then any time you actually need it, check that you've agreed on as much detail as you needed for the task and not less.

The person inviting you to a picnic "next week" might need to know about Time Zones if they live some distance away. The requirement to update the CSS on the web site to match a new company logo might need to know about Colour Spaces. But that picnic invite doesn't care about Calendar systems or Leap Seconds, and the logo mandate doesn't care about Sub-surface scattering or a Quantum theory of light.