It's bonne dix neuvieme anniversaire, you retard.
Actually, the normal way to say it would be "Joyeux dix-neuvième anniversaire" though sounds very formal. If it was me I would just say:"Bonne fête!!"
Saying "Bon anniversaire" is a bit like wishing someone a Happy Christmas. Not grammatically wrong but it's just not something we usually say. And keep in mind that despite what the liaison would leave you to believe, "anniversaire" is a masculine noun.
How big is the difference between French and Canadian French? I mean grammatically?
Grammatically not very different. There are a few worker's professions that can be feminized in Quebec but not in France and that's about the extend of it. For example, if we ought to follow the recommendation of
L’Académie française, "Annie is a doctor" would translate as "Annie est un docteur.", but in Quebec you must say, "Annie est une docteure", unless you want to be crucified but a mob of feminists.
The real difference is when it comes to idioms and slang. There are a lot of expressions that we use but not them and, to a lower extend, the reverse is also true. Any american movies are translated by Frenches and then watched by Quebecois and it's normal that we and up with some of their expressions. We don't always use the same Anglicisms, like for example there is a joke we sometime make that the difference between the two accents is that "To park in the parking lot" would translate as "Se parker dans le stationnement" in Quebecois slang but as "Se stationner dans le parking." in France.
And I think there is a law somewhere saying that we can't talk about the differences between the French French and the Quebecois French without mentioning that
Quebecois like to use religious swears: "tabarnak, criss, osti, calisse, [saint-]ciboire...".
