Toronto has an efficient public transportation system that includes subway lines, buses, and streetcars. Get a TTC Day Pass ($13) for unlimited travel across the city. Alternatively, ride-sharing services such as Uber and Lyft are also widely available.
If you have more time, consider visiting the High Park for outdoor activities or the Ontario Science Center for interactive exhibits. If you have less time, consider skipping the Nathan Phillips Square and taking a shorter visit to St. Lawrence Market. Pack comfortable walking shoes during the trip as many attractions are easily reachable on foot.