1. Get your passport, credit or debit card ready, and read the help document. Apply online for an eTA.In addition to your passport, you may need a travel authorization such as a visa or an Electronic Travel Authorization (eTA) to enter Canada. A consent letter demonstrates that a child has permission to travel outside Canada from every parent or guardian who is not accompanying them on the trip. You'll follow the same 3 steps to enter Canada: Step 1. Pre-arrival: Use Advance Declaration or complete a Declaration Card. Know what documents a child needs to travel to or from the U.S. All children, including infants, must have their own travel documents. USDA's Animal and Plant Health Inspection Service (APHIS) protects the health and value of U.S. agriculture and natural resources. Individuals interested in applying to become an HPI can fill out and submit the HPI Application below. The AAG provides a formal invitation letter to help with the visa submission process.