The answer depends on the citizenship of the foreign worker.
Some foreign nationals require an eTA or visitor visa to be authorized to travel to Canada. Therefore, foreign workers from eTA or visa-required countries will need this document in addition to the work permit.
A foreign worker who applies for a work permit from outside of Canada (meaning at an embassy or consulate) will be issued an eTA or Temporary Resident Visa at the same time as the work permit.
If you are a foreign national interested in working in Canada and would like assistance with understanding the process, including what documentation is required to travel to Canada, please contact Toronto immigration and employment lawyers, Sultan Lawyers, at (416) 214-5111 or via email to mlahert@sultanlawyers.com.