Do I have to speak English or other languages in addition to French?
While French is the official language, English is very present in Québec given the North American context of its economy and the strong presence of an anglophone minority.
In order to practise your profession, some employers may require you to have a functional knowledge of English or to be bilingual. This requirement is particularly common in the Montréal region, but also exists in other regions of Québec.
Several options are available for learning French / English. For example, you can take on-site or distance courses offered by educational institutions or language schools.
If you are proficient in a language other than French and English, this will definitely be an asset that you can promote. However, mastering a third language is rarely required by employers.