Yes, today is Thanksgiving Monday in Canada. It is a statutory holiday across the country. Government offices, banks, and most businesses are closed for the day. That includes Toronto and Ottawa. Retailers are hit or miss today, so call ahead before you go out.
In the United States, today is Columbus Day, also a federal holiday. Some states recognize it as Indigenous Peoples Day. U.S. stock markets and many banks are running normal hours, but hours may be shorter than normal.