No Carrier. What does this mean?

I am looking to buy the current iPhone XR (on the Canadian website), and ship it someone in Canada. I see no carrier option (the category doesn't appear) on checkout, so does this mean that the Model A1984 will ship fully unlocked and will work with ANY compatible US & Canada network? Does this work with GSM, CDMA, and LTE seeing as there is only one model for the US and Canada? My apologies if this is confusing, I am very uneducated on the topic of cellphones and carriers etc..