That's the problem with French: everything you learn in school or listening to the news anchors will be something different from what you actually use in everyday life. So you have to re-learn it
That's not unique to French, nearly every language has some pretty large differences between the colloquial language and the more formal language. Arabic is particularly difficult is this regard because modern standard arabic serves as the official language, but everyday speech is done in the individual dialects. But the differences between the dialects and MSA are pretty large, to the extent that a lot of linguistics think that "arabic" should really be considered as a family of closely related languages. So the situation is akin to the governments and media of France, Spain and Italy working in Latin while people in those countries continue to speak their respective languages.
I thought it was only French that was like this. But the English I learned in school wasn't anymore representative of the British-English (try watching 'Skins' or The Office or Extras) or Australian English (took me some time...). And then even in the US. After years of watching American shows without subtitles, first time I read 'to kill a mockingbird' or 'catcher in the rye' was a shock. So much vocabulary I didn't know... And it was only high-school level English!