Like bowball said, ArriveCan is a smartphone app that you download onto your smartphone. You enter information in it regarding what border crossing you are using and when, if you are coming as a tourist, business, student, etc., your passport information and vax information. It's easiest if you know how to use the camera on a smartphone to take a picture of your passport and vax card. In essence this info is similar to if you fly somewhere internationally and fill out paper work on the plane for your arrival but it's just in a phone app. I've done it a couple times and found it pretty easy to use. If you are going as a couple or family one person can enter all the info for related travelers. Aside from the app the rest of the crossing is the same as always with the usually questions on what you plan to do in Canada, any weapons or produce.