Canada features as a dream destination for students and young adults seeking a new life abroad because of the ease with which you are welcomed there and the benefits given in education and healthcare. However, everything is not as rosy pink as it seems to be. First and foremost, it is extremely expensive to stay in and you will likely be paying a lot of taxes. Secondly, it is not as though you will get a job right away. A lot of people go there and start with odd jobs like working in a store or a restaurant just to have some financial support. I have read articles where they mentioned that work experience in India does not necessarily make it acceptable eligibility for a job in Canada. You have to start from scratch and the report mentioned that without referrals it is really tough.
Coming to the specific case of your daughter, do not push her into taking up something that she is not interested in or does not have an aptitude for. If she has a minimum interest in Science, why push her into doing a nursing course? Same for Hotel Management, which is a course that covers a lot of aspects. It is not just about food and beverage, cooking and cuisine. There are learning modules that include HR, Marketing, etc depending on the curriculum of the institute where it is studied. If your daughter is very clear about what aspect of hotel management she wishes to take up a future career in, then only she should go in for it. Otherwise, it is a total waste of time. I am saying this from what I know of somebody who did a full-fledged IHM course, got a placement with a retail chain, had a very tough and hectic schedule with no leave, got laid off due to the pandemic and is now pursuing a totally different line of skills. It is not that the course is not good. There are hotel management students who have done well, such as, setting up a bakery or taking up work in event management, but that is because it is genuinely their interest. It is also not easy to move up the career ladder even if getting entry into a top hotel chain. One can remain for years as a junior executive only and not rise at all.
You mentioned that your daughter is good at English, has studied French and can learn the language more. So why not let her focus on what she is good at? Let her take up French at Class XI and XII as well, maybe even graduate in French. You see, if she is fixed on her goal of going to Canada, both these languages will be a huge plus point for her since other than English, French is the main language out there. It is not only in terms of communication that learning it will help her but also in terms of job prospects. My sister mentioned that openings for language specialists come up in international organizations such as the United Nations and its allied associations, such as UNICEF, UNDP, etc. There are jobs for translators, educators, writers, etc. She can even check out internship offers at these organizations once she completes her academic studies. I also suggest that if she has an outgoing personality, loves interacting with people and is interested in travelling, she could take up a course related to becoming a tourist guide. Knowing at least one foreign language is beneficial for this kind of career (again, mentioning here not to force her, let her decide). Whatever choice she makes, I would strongly advise your daughter to take up a professional French language course through Alliance Francaise. It is a centuries'-old international organization (a couple of my school classmates joined it to enhance their French skills) and they have centres all over India. Your daughter need not start at the beginner's level if she is already confident with the language since she has already studied the basics and you have indicated that she may have a flair for it. She can check out the intermediate level. At present, online classes are conducted but if the centre opens, register ideally at one that is nearest to your current place of residence. [refer - https://madras.afindia.org/af-network-in-india/]
As for when to move abroad- after graduation would be my advice because your daughter will be more mature then and prepared to cope better at that age with all the challenges that will come up with the move to a foreign locale, the biggest challenge being culture shock.
To summarize-
1. What subjects should she select in class 11? - Go for the Arts stream, ensure English and French options are there.
2. What are the career scopes (in Canada) with those subjects? - As per what I mentioned above for job prospects.
3. Is Hotel Management or Nursing a good choice for her? - No for both. Don't go by just what Google says about popular courses/careers! Let your daughter focus on her own interests and strongest skills.
4. Should she move abroad after class 12th or after graduation? Why? - Maturity comes with age, so let her go after graduation only.
Best wishes to your daughter in achieving her goals.
When you make a commitment, you create hope. When you keep a commitment you create trust! ~ John C. Maxwell