You'd think it would be simple. You send in some personal details. The government looks them over. Then gives you a yea or a nay. But life always seems to be a bit more complicated than it should be.
The national immigration systems of the world were all established with essentially the same aim: permanently let into your country those whom you believe will make good lasting contributions to your society, temporarily admit those who are unlikely to do any harm (perhaps giving some of them study or work permits), and keep out those whom you deem undesirable.
The challenge for immigrating permanently to Canada or even for coming temporarily as a visitor, student or worker is that instead of one simple form on which you write some personal details, and check off a couple of boxes for what kind of status you are seeking in Canada, there are reams of forms with obscure numbers, names which aren't self-explanatory, and a host of choices that must be made for the best application type and route. But it is possible to distill down the process to the basics.
1. The three main factors that keep people out of Canada relate to: (a) criminal history, (b) health condition, and (c) financial capacity. If you haven't committed criminal offences in the past, are healthy, and have money, Canada will probably let you inside its borders - at least on a temporary basis. Though there unfortunately remains unjustifiable discrimination against certain source countries, or personal circumstances, even when the previously mentioned three criteria aren't problems.
If you do have a shortcoming on one or more of those three grounds, you need to carefully study the Department of Immigration, Refugees and Citizenship Canada website and perhaps speak with an immigration lawyer to determine whether you will be excluded from Canada, and if there are any ways to get around that exclusion.
2. The three main ways to temporarily enter Canada are as a (a) visitor; (b) student; (c) temporary worker.
Citizens of a small number of preferred countries don't need visas to enter Canada as visitors, and can just show up at the border - passport in hand - and usually get a stamp permitting a stay of six months. It's then possible to apply to extend that stay for additional time. You'll still be subject to those three factors which exclude people from Canada, but they won't be as strictly applied if you're only a visitor.
Everyone else in the world will need to apply for a visitor visa in advance. From some places, these visas are very fast and easy to get. From other places, they are almost impossible to obtain. The difference largely rests on how many people want them, how much staff is devoted to issuing them, and Canada's assessment of how likely you are to return home at the end of your visitor period.
You'll need to be able to qualify as a visitor in order to additionally get a study or work permit. Study permits aren't too difficult to obtain if you are able to prove admission to a legitimate education institution in Canada (you need to carefully check out in advance the status of the school and program you will be attending - there is lots of misinformation out there) and the financial means to support yourself while studying in Canada.
Work permits are more difficult to obtain because of the way employers who wish to employ foreign workers must demonstrate that they can't find a Canadian for the job. Clients frequently come to our firm who are legitimately in Canada on visitor visas, want to work legally here, but have become very frustrated when employers who are favourably disposed towards them can't obtain foreign worker authorizations because they don't understand the system for obtaining what's known as a favourable Labour Impact Market Assessment.
3. There are two main ways to permanently enter Canada: (a) through an independent/economic/business application or (b) through a family class application.
Although there are various schemes going by different names where independent/economic applications are concerned, and increasingly the provinces have their own schemes (though provincial program applications are still largely processed through the federal government with the exception of Quebec) the fundamental distinction in permanent resident routes is between these two classes.
The family class is mostly for spouses and dependent children. There are a few exceptions that could extend sponsorship to other relatives, but generally this class has been getting more and more narrow - for instance, sponsoring parents and grandparents is now extremely difficult, and instead the government promotes a 10 years SuperVisa for them, which permits stays of up to 2 years at a time.
The independent/economic classes generally require that you have work or business skills that are in demand in Canada, or money to invest in starting a business in Canada. There are lots of options here, and even if you don't qualify when you first examine the possibility of coming to Canada independently, it's worth checking again in a year or two to see if there might be new programs that you could more easily fit into.
4. As a Canadian immigration lawyer, the best tip I can offer to anyone reading this post who's interested in spending an extended time in Canada (or who wishes to enable a relative to do so), is don't become overly fixated on obtaining permanent residence at the cost of ignoring much quicker and easier temporary residency routes.
For example, sometimes foreign student or temporary foreign worker programs in Canada can offer an easier path to permanent residency. You'll get to Canada much more quickly than waiting years for a permanent residency application to be processed, you'll be able to learn whether Canada really suits you before you making a permanent commitment to it, and your permanent residence application may receive preferential treatment after you've worked or studied for a number of years in Canada (depending on the type of work and level of completed studies).
The same goes for bringing parents or grandparents to Canada. If they're already in their 70's, obtaining a ten year temporary residence SuperVisa for them, where they can continuously remain in Canada for up to two years a a time, might have a much better practical outcome than waiting years for a permanent residence sponsorship application to be processed.