Hi,
"...being totally immersed in another language." That's the good part. The bad part part is: are you ready for that? Unless the course is a beginner, ie lower division course, I am going assume it's all in French. If you have finished your second college year and are now taking this summer course abroad in southern France, the course will be in French. I would be surprised if it isn't. My suggestions are:
1) don't be afraid of making mistakes and, above all, being corrected. After all, who is the beneficiary of the correction? You, and you'll know better the next time. The more you get corrected, the better it is for you the next time. 2) Keep plugging away at the French, write your notes, daily reminders, instructions, even your "diary" etc, etc in the language so that you start dreaming in French.
3) Don't be intimidated to speak when the chance presents itself? 4) Don't rely on "their" knowing a certain level of English in order to communicate, since you think your language knowledge is too "modest." That's not good enough.
5) Get down the grammar, I found the irregular verbs to be most taxing. 6) If you can't say it correctly, then know how to write and spell it correctly. 7) Finally, don't give up the efforts, period...since you're the one benefiting from this immersion experience. Forget about it being intimidating, daunting, or even a frightening experience when everyone is chirping away en français and you feel linguistically inadequate...so what? You're there to learn, absorb, and improve. That's exactly what will happen.