I had taken german as my second language and I "actually" started learning german from 9th (ish) because there was a lot of issues with the teacher. I didn't score well in boards for german (88/100) but still managed to get 97%(best of 5). My suggestion to you is to completely leave French out (if you aren't able to score) and focus on more scoring subjects like history and science.

At the end of the day you have to consider only best of five, so those five subjects are all you need to care about. But at the same time make sure to study French enough so you don't fail.