It will depend off whether you applied for work permit from within canada or outside canada. If your applied as form within Canada, you will be send a revised WP. If you applied for WP outside Canada, you will be issued an eta and a WP depending on your country of citizenship.
Renewing your work permit
If we issue your renewed work permit on or after May 1, 2017, we will automatically issue you an eTA as well.
If we issued your renewed work permit before May 1, 2017 and you don’t already have an eTA, you will need to get one before you return to Canada by air.
If you’re from a visa-required country
You’ll need a valid visa and a valid work permit to return to Canada to work. You don’t need a valid visa if you return directly from a visit only to the United States or St. Pierre and Miquelon. You must
re-apply for a visitor visa if your visa:
- has expired or
- was only valid for a single entry to Canada
Starting May 1, 2017, eligible citizens of
select visa-required countries will receive an eTA when they renew their work permit. The eTA is electronically linked to the passport you used to renew your permit and is valid for five years or until your passport expires. You can only use the eTA when you fly to, or transit through, Canada by air. You will receive a letter from us with information about your eTA number and expiration date.
If you already have a valid visitor visa, you can use it to travel to Canada until it expires. A visitor visa will let you travel to Canada by plane, car, bus, train or boat.
See
https://www.canada.ca/en/immigration-refugees-citizenship/services/work-canada/permit/temporary/extend/travel-outside-canada.html
