The knowledge of the language at C2 level allows you to not only communicate freely with native speakers in all spheres of life but also to teach the language in educational institutions.
At this level, you understand native speakers you encounter completely, both in written and oral speech. Sometimes you make minor mistakes, but still, the level of language proficiency is very close to the level of a native speaker. You can understand the subtle nuances of intonation, speaking speed, and choice of expressions even in difficult situations or texts.
Another important level characteristic is fluency. To use a language fluently means to do it freely, without pauses, to speak as in one's native language, and at C2 level you can do that. C2 level gives you the ability to speak spontaneously and instantly, using a rich vocabulary. You can communicate on any topic and use idioms and slang phrases, you possess high skills in a written language. You can easily describe your ideas in correspondence or essays.
Since C2 is the highest level, you can now use the language in any part of life - from everyday matters to professional environments where you need to know the complex specialized vocabulary. The possibilities of using a foreign language for a person with this level are limitless. You know the language at the level of a native speaker, so you can consume all the same information and communicate unchallenged.