Fashion is a very different bag of bananas to weddings and photojournalism, but I'm sure you don't need me to tell you that. It's a team effort, between photographer, stylist, hair/make-up, art director and models (though not all shoots will use all these roles, and not all play equal parts - it's different every time).
You need experience, and if Montreal is as tough as London, you need to get a break by first offering to be an assistant (probably for free to begin with) for a fashion photographer.
Some people go it alone from day one, and just begin shooting, but there may not be the fashion culture in Montreal to allow you to do this, as it very hard even in the fashion capitals of the world. If you do, you will have to try to team up with some of the other types of creatives I've mentioned.
Lastly, don't just throw away what you've learnt already, try to incorporate it in your work. This is what could make you unique (what you've learnt from weddings and photojournalism) but be prepared to accept that it might also just make your work stink, and actually you do need to just begin again.