I thought that airlines has to give information in advance about the passenger to Canada like pasport information, who paid the ticket and also thought itenary of the ticket. I'm not 100 procent sure about what information they need, but to be save I have booked for myself a one way ticket to land in Canada. First I thought to book a 2way ticket and just make the return flight to Canada, but I found out that my airline cancel the return ticket when you don't show up to the first flight. I booked the one way also for not to have to give the answer why I booked a return flight, that it was cheaper to take a return flight. I plan to land in May.