Knowledge of the two official languages is largely determined by geography. Nearly 95% of Quebecers can speak French, but only 40.6% speak English. In the rest of the country, 97.6% of the population is capable of speaking English, but only 7.5% can speak French.[89]
(from https://en.wikipedia.org/wiki/Official_bilingualism_in_Canada#Personal_bilingualism_in_Canada)
Jesus fuck, those numbers are abysmal.
That depends on your definition of "united", doesn't it? The United States of Mexico or America are definitely "united" into one country, i.e. there aren't really any serious secessionist movements, nearly all citizens speak the country's main language etc. The USA are politically divided, but the divide doesn't follow state borders that closely and many states are still swing states or flipped in the last 1-3 decades.