The attestation papers are provided by the province or territory that you want to study in. They basically give you permission from the province to study in their province. If you are enrolled in a crappy for-profit college, you probably will not be given attestation papers.

Because this requirement is brand new and the details may vary from province to province, it is best to ask the school that you received your Letter of Acceptance from, to direct you to how you obtain attestation papers.