There seem to be some misunderstandings here. I'll start with clearing them up.
Canada is officially bilingual, and has been since its founding. French in Canada is a minority language, and part of the founding compromises was that the central government would support that people who speak French would be able to function in public society. They had a fear, pretty justified, that without central support their language and culture would go away; before joining a larger government, they wanted some security against that happening.
This also led to some other compromises, like the location of the capital. If you are familiar with US history, the Washington DC compromise (on the border of the North and South) was similar.
The requirement on Federal government jobs to speak French (and English) is:
In a communication job, the Federal Government must be able to communicate in both French and English with the public. Both are equally official and full featured. The Federal Government must also provide full services to the public in both French and English.
As a Federal Government worker, outside of communicating with the public and supervising other workers, you are free to choose if you work in English or French.
But point 2 means that as a supervisor of Federal Government workers, you must be able to work in both English and French. Otherwise your reporters will be forced to learn your language to work under you.
This means that most non-supervisory workers don't need to be Bilingual. People in communications posts and service posts either need to be, or the task needs to be split with someone who is fluent in the other language; there are people whose job it is to have enough expertise to translate/copy edit translations of subject-specific press releases, for example.
In a sense, this is a Workers and Citizens rights issue. Citizens freedoms are viewed as more important than Workers freedoms, who is viewed as more important than Managers freedoms (to live using the language of their choice).
Canada's immigrants come from a mixture of English, French (mostly ex-colonial holdings) and non-English/French speaking countries at this point.
English is the dominant language in media, due to the global bias towards English and that the majority of the country speaks it. French is probably second place. Immigrants are significantly more likely to learn English as a second language than French, especially outside of Quebec.
There is no formal requirement than the PM speak French in the law. It is custom, and not being able to speak the first language of 25% of the Citizens of the country would be rude and electoral suicide. (Many marginally fluent people who want to be PM take extensive language training "on their own time".) The jobs where the law demands you speak both fluently are civil service jobs, which are rarely described as "high profile".
The Governor General is a figure head (and an emergency Government escape pod), and is expected to be fluent for political reasons.
Ministers (politicians a step under the Prime Minister) are expected to be somewhat fluent, and to spend significant effort improving if they aren't. They communicate with their civil service organizations via their Deputy Minister, a Civil Servant, who is going to be functionally bilingual; but if a Deputy Minister is in the news, it isn't usually a good thing: either they screwed up badly, or are resigning in protest over a government action. So I wouldn't call them "high-profile".
In the Federal Government, people who want to be upwardly mobile into the executive are expected to put significant effort into learning the other official language. The Civil Service even pays for classes, sometimes including immersion training (less often nowadays, it was too expensive) to teach people to be able to work effectively in both languages.
It is a significant investment, but except in exceptional situations, is more than a decade between entering the Civil Service and reaching a position where you would be expected to be able to supervise other employees in both languages. A concerted effort over a decade will permit most people to pick up at least halting fluency in a second language; if your supervisors consider you worth investing in, they can fund you for further intense language training.
The shortest time I know of that someone made it from halting "high school" French to fluent (according to the tests) was a week, but that was a 6-language fluent linguist who knew multiple romance languages. Usually it is many months of study or longer.
Now, due to the higher chance people whose first language is French to be bilingual in English than vice-versa, this means that more Francophones work in the public service (as a percent of their population) than Anglophones. It also means than in Canada's capital city, 80%+ of Anglophone elementary school children are in French Immersion, spending 75%+ of their instructional time being taught in French.
For Immigrants from India, the government of Canada offers subsidized "ESL" and "FSL" courses you can take as an adult, both to migrants and to the general population. It is a lot of work. Immigrants from areas that speak neither French nor English generally put that work in in order to be able to work and live in the country; they are, in a sense, worse off than Indians.