First you need a Federal Skilled Worker Visa. You also need the appropriate level of education and work experience, and be able to pass a criminal record check.
One of the main requirements of getting a Canadian Federal government job is to be a Canadian citizen. You would need to find out how to become a citizen.
Well you need to be living in Canada for starters. I always thought you had to be a Canadian Citizen but that I could be wrong. You also need a résumé. There are a number of government segments' who do the hiring it.
You must go to the local MLA of your desired town and get a form that you write out. Then, when they look at your form, they may ask for a criminal record check. Just to make sure that you haven't done anything bad.