Yes, today is Thanksgiving Monday in Canada. It is a statutory holiday across the country. Government offices, banks, and most businesses are shut down for the holiday. That includes Toronto and Ottawa. Retailers are hit or miss today, so check before heading out.
In the United States, today is Columbus Day, also a federal holiday. Some states mark it as Indigenous Peoples Day instead. U.S. stock markets and many banks are open today, but hours may be cut short.