You are right in that you would need to first secure a job with an employer in Canada, and thereafter apply for the relevant work permit and visa. You can find more info on our Work Permits for Canada page. However, as you say, it's a pretty complicated process - for example, the employer would have to prove that a Canadian citizen would be unable to do the job you'd be doing.
There are a number of different types of visas, though, and you may find that you are eligible. We have a list of the most common on our Visas for Canada page.
Best of luck!