Going from beginner to C1 in a year in a semi-immersed environment. Give me a reality check...

My partner and I are based in the US and -for a variety of reasons- are looking to get out of the country for at least a year. We are considering several paths; remote work, teaching English, and graduate school.

I've always wanted to break into the international relations realm, but even after one graduate degree, I've realized how far language skills matter (I know someone who had a 2.38 undergrad GPA but got into Georgetown SFS because they spoke Farsi). So that's the main goal of this idea- become C1 in a valuable language.

Now, I'd have to take my courses in English but would plan on a, "no english except when needed" rule outside of the classroom. I'd also look into language courses in-country.

Our top choices are Turkey, France, and Spain and learning their respective languages.

BUT...give me a reality check... Is it possible to become C1 in a semi-immersed environment?