You can definitely develop the “ear” on an immersion in a foreign country. But you need to interact with local speakers, not just other lang students.
My problem was never speaking or listening. My hs jumped me ahead based on the summer program level and testing, but I missed the hs year where higher reading skills are developed. My peers could tackle a novel.
Hmm, otoh, I probably comprehended and spoke on a higher level.
So just beware what you wish for.
Are your parents native French speakers or ? Was it your first language?