You check with your country travel outside the country
and they should have all the information, previous to your travel, there are also warnings and important info about traveling to some countries and for Canada it's updated regularly.
Apply 3 days before landing in Thailand at the proper website and they will send you a QR Code to be scanned at emigration on entry.(this a learning process as I didn't do it yet but that's my understanding and if I make an error, let me know)🙂🙏