It would be a very good idea to get a guidebook to Paris and work out from this the sights you really want to see. There is so much to see and do in Paris that it's really impossible to list all items. Also, what you see depends very much on your interests. So get a guidebook, make up an itinerary that suits you, then go and enjoy. But, be flexible. You might want to just sit in a park such as the Jardin de Luxembourg or Jardin des Plantes, or walk along the Seine, or visit an off the beaten track bistro. Do what you want to do, not what others think you should do.