Let's review. Do you remember how to say "I'm going"? Je vais. And how to say "to la comtesse"? À la comtesse. Do you remember how to say "I'm going to la comtesse"? Je vais à la comtesse. And how to say "on foot"?
À pied. Do you remember how to say "I'm going to la comtesse on foot"? Je vais à la comtesse à pied. Now you know how to talk about transportation in French. And you can move on to the practice. Au revoir !