SandandSeas, I am Canadian, so I have always just used ArriveCan on the way home. I snipped this from the Government of Canada website. I am not sure of your situation (flying into Canada, or just port stop), so I included a couple of scenarios. I do think it is handy to have the app on your phone, if possible. If not, you could start it at home on your PC I think. Here's the relevant info for cruisers. I hope this is helpful:
Entering Canada by land or air before embarking on a cruise
You must complete your ArriveCAN submission before entering Canada, no more than 72 hours of boarding your flight or before entering Canada by land.
If you’re flying in to join a cruise immediately, enter the address of your terminal.
If you’re not joining the cruise immediately, enter the address of your hotel.
You must also submit a second ArriveCAN submission no more than 72 hours before boarding the cruise. This applies even if your second ArriveCAN submission is within 72 hours of the first submission.
Upon your entry to Canada by air or at a land border crossing, the border services officer may notify you that you’ve been randomly selected for a mandatory arrival test.
Mandatory random testing is part of the Government of Canada surveillance program to track the importation of COVID-19 virus into Canada, and identify new variants of concern.
Boarding cruises and shore excursions
Some requirements for boarding a cruise, either at the beginning of the cruise or as part of a shore excursion, may be different depending on where you are boarding and which countries your ship will visit.
Mandatory requirements for all travellers, including Canadians, include pre-embarkation testing and can include ArriveCAN if your ship is coming to or returning to Canada.
Choose the scenario below that best fits your cruise plans:
Starting an international cruise in Canada or arriving by cruise from another countryCruises that are staying in Canadian waters or not returning to Canada
Providing proof of vaccination
You’re required to upload your proof of vaccination into ArriveCAN before:
you enter Canada, or
embarking on a cruise that is travelling outside Canadian waters (for example, if docking in the United States for a shore excursion) or a cruise, or
embarking on a cruise that will dock in Canada at any point in the itinerary
This applies to all travellers, including Canadians. ArriveCAN is mandatory and free for all travellers entering Canada, regardless of citizenship or vaccination status.