language in profession

[ANHNTT1]

I have just received financial support for studying Phd from my organization where i'm working for, according to that are necessary condition: time of dedication, time to finish (maximum 5 years) and result of studying. The university i will come is École polytechnique. But my problem now is "French" (  i only get TCF under 300) while my recent job requires travelling much and i don't have much free time. I don’t have enough time for pre program (i only have 5 years according to conditions), i really worry because i know that if i don’t have good language skills, it will be very difficult to follow and this will negatively affect my financial support i could receive. I write this topic to hope that someone of you could give me advices, what should i do in this situation , could i study language and research at the same time?

Please help me!!!!!!