In Pudong, you could do a short visit in the Lujiazui Area (the Pearl Tower), as well as do shopping. Then, you could take the bund sightseeing tunnel ti Puxi for visit. Or, you could take a ferry to the Bund, and then walk to the Nanjing Road until to the People's Square. Here, you could go to the Shanghai Museum, a very good place! Well, it is suggested that you refer to the list at https://www.travelchinaguide.com/attraction/shanghai/