Hello Allison and welcome to San Francisco! I worked in SF for 34 years and now live just across the Bay in Oakland. If the weather is nice, a long walk from the cruise terminal along the Embarcadero is about as good as it gets. I prefer the South direction toward the Bay Bridge, taking you past the lovely Ferry Building which is now a food market. They there are parks, waterfront, outdoor art and splendid views of the Bay and the city. You will end up at the baseball park. In the North direction you go past a number pf piers, including Pier 39 with tourist attractions and seals and then on to Fisherman's Wharf. There are other good walks in town, but these 2 are easy from the cruise terminal.