How can a person switch from Arts to STEM? A person (30-35 y/o) has an MA in History and works in a Starbucks shop in Canada or drives Uber. Now, he wants to study MSc in CS/CSE in Canada for better employment.
What/how would be the pathway to accomplish that in the shortest time period in North America?
I admire the enthusiasm, that's for sure. The practicality of the situation, well that's different, but have a go! If the goal is to work in IT, which it sounds like it is, I'd skip the MSc altogether and focus on, for example, software development, system administration, IaaS via AWS or Azure, network administration, whatever. The shortest path, as you ask for, requires laser focus at this point. Best of luck to all involved!
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There are numerous avenues in IT. Two roles that might not be obvious, but perhaps worth consideration for someone with a nontechnical background, are business analyst and scrum master. These tend to require broader skills, maybe with more emphasis on interpersonal skills, than others.