What is an eTA?
An Electronic Travel Authorization (eTA) is an entry qualification for visa-exempt outside citizens traveling to Canada by air. An eTA is online linked to a traveler’s passport. It is valid for up to 5 years or till the passport terminates, whichever comes first. If you get a new passport, you need to get a new eTA.
With a true eTA, you can move to Canada Whenever You want. You do not need an eTA for travel within Canada.
An eTA doesn’t promise entry to Canada. When you come to Canada, a border services officer will ask to see your passport and other certificates.