You show up at your first departure airport for an international trip. The lovely agent doing your document check says, "I'm sorry but you are not able to board the plane today". After you pick yourself up off the floor from the shock of this news you learn that you needed an Electronic Travel Authorization for the country you are travelling to. While your travel agent can certainly help guide you to ensure you have the correct documentation the traveler is ultimately responsible to ensure they meet all requirements to enter their destination country(ies). Where to start?
There are official resources for Canadian passport holders to understand the requirements they must meet to enter all countries and whether, technically, they should even enter a country. There is a wealth of information on the internet that will guide you and potentially fleece you out of money with exorbitant fees, false documentation, etc.
Canadian passport holders should always start at the Government of Canada Travel Advisory webpage:
https://travel.gc.ca/travelling/advisories
One major benefit of starting here is if you need a visa, electronic travel authorization or any other documentation to meet entry/exit requirements the links to these processes on this site are official.
You should also check the Sherpa Travel Requirements website for entry/exit requirements. The details are sometimes a bit more granular. On this site you need to ensure you select the country of your passport as it will often default to a US passport:
https://apply.joinsherpa.com/travel-restrictions
Do not rely on random sites to apply for documentation you find through an internet search as they may not be current, can have intentionally erroneous or out of date information or are flat out fraudulent and will separate you from part of your travel budget.
All you have to do is review the entry/exit requirements for each of your destination countries. You will know whether you need any more documentation than your passport, how much time you require on your passport and you can also confirm if there are any mandatory vaccinations required to enter a country. Don't let this be the showstopper than breaks your holiday. Your travel professional can help you navigate this and guide you to visa concierge companies that will help make sure you have everything you need if you do not want to deal with required applications. This professional service is of course for fee.
IMPORTANT: Travel requirements change without notice. Always check a month out from your trip to ensure entry/exit requirements are the same as when you booked.
Passport Tip: If you have 6 months remaining on your passport from the departure date of the country(ies) you are visiting this should meet entry/exit requirements. And, if you are going on a cruise almost every cruise line policy requires you have 6 months or more remaining on your passport from your disembarkation date. They can refuse boarding if your passport does not meet this requirement even if the country only requires a shorter period of passport validity.
Note that all travellers are responsible to ensure they meet entry/exit requirements. While your travel agent can help guide you the onus is on the traveller to meet requirements.