Where to enter the United States?

Generally speaking, more people can enter the United States from Los Angeles, new york, Chicago, Seattle and Atlanta.

If you fly with Air Canada, you actually entered Toronto. But you need to carry your luggage when you transfer, so you'd better know the transfer time. A few years ago, the customs inspection was very loose. If you want to bring something to eat secretly, you can go here, but I haven't been on a plane in these two years, so I don't know.