Of course will help you! Vueling for instance require Spanish Icao level 4! But one thing is bilingual (C2 level, icao level 6 is not bilingual) and another thing is having a good knowledge and level of some language!
I Can speak english for instance But I am not bilingual actually I am just ICAO level 4 so my level of english is really poor! Luckily I am just a PPL from now!