I was very lucky growing up, and my little middle school in my little village in Nova Scotia offered French Immersion (late, started grade 7).
Sure, some of my teachers were anglophone, but the rest were Acadian. When I went to university I didn't think much about it, but soon discovered that I was functionally and operationally bilingual. I continued to study French at university where all of my teachers happend to be from la belle province and graduated.
Now I'm a professor in France. I've been doing this for about 17 years. My students greatly underestimate their level in English, yet here I am correcting 750-word essays written by 1st year students who have only "studied" English for an hour or two a week since middle school. Are they good? Meh... But they are better than they imagine.
Canada is supposed to be bilingual. I've seen different numbers fly around over the years regarding the percentage of bilingual Canadians. How about you, are you bilingual? How bilingual?
Addendum:
These maps are not directly related to the question, but I came across them while looking things up.
This is from 2016. I like showing this to my students. They always ask me why I bothered learning French.
And this is from 2021 and is a little bit related to my question, but only covers English and French.
Northern Ontario. Fully fluent in French and English, written, spoken, and between the lines. French Catholic schooling. French at home and at work. I realize I am the exception.
I agree with other comments on here, like many other skills, if you don't use it everyday that skill will rust over time.
Here's poster that shows French language schools across Canada. It is rather dated but it may somewhat answer the question.