Canada

[Gaysha]

^Maple Leaf train

[rics]

Is there a train from Toronto to New York? 

You can take the Via Rail train at Union Station in Toronto going to NYC
Or you can take the bus (greyhound, megabus) from Toronto going to NYC (port authority bus station)

[LollaMaden]

I took the bus from Toronto. It was amazing because I could enjoy the views.

[AlexaAlly]

The good thing about Niagara Falls is that you can visit Canada as well. It's totally worth it since there are many things to be seen there as well. Make sure that you are going to pack some winter clothes. I was with a tour from https://www.viator.com/en-CA/tours/Toronto/Niagara-Falls-Small-Group-Day-Tour/d623-39437P1 when I was there and I've made the mistake of not packing a jacket. Now, let me tell you that I've got sick so bad that I couldn't even enjoy the rest of your trip. I even had to go to the hospital once I've got back home, so make sure that you will be dressed properly