I have just returned from a trip to Shanghai, and I think there are several places worth visiting. You can choose the route like this (for reference only, I have visited it like this and think it is not bad).
Starting point: On Nanjing Road, you can take the subway. When you get there, you can walk all the way to the Bund. Nanjing Road is a shopping place, like Wangfujing in Beijing. Things are more expensive, but I think the buildings in Shanghai are very distinctive, and Nanjing Road is one of them. You don't have to visit all the shopping malls, but you must see the buildings.
Go all the way to the Bund. You can walk there slowly. If we leave at 10 in the morning, it will be around 12. You can see the Oriental Pearl on the Bund and take pictures. Then I crossed the river. There are several ways: first, there is a tunnel, 45 yuan, and there is nothing meaningful in it. I don't advise you to do this. The second way is to take the subway, but when I take it, people are super crowded, so be careful in the subway. The third is by boat, which is more affordable, 50 cents a person. But it's a long walk along the Bund. By the way, you must not wear high heels when you go to Shanghai. Even wearing slippers is fatal, hehe.
Then I saw the Oriental Pearl and Jinmao Tower. The two are relatively close. However, I don't think it's necessary to go up both of them. The last one will do. My suggestion is Jinmao Building, and there is a post office on the 88th floor. It is the highest post office in the world. You can buy greeting cards for people you like. Very meaningful, but greeting cards and stamps are more expensive.
There is an aquarium next to the Oriental Pearl. You can also go and have a look.
In the evening, there is a cruise ship. Generally, it takes 1 hour to swim along the Huangpu River, and the boat with more than 80 yuan an hour is ok, but the one below is not so good. And when you take a boat, you should prevent being cheated.
It is estimated that the round trip will take 1 day. I hope I can help you ~ ~ ~
Other places worth visiting are Xintiandi, where there are many foreign restaurants, bars and discotheques. In the evening, many foreigners are very busy ~ and there are ancient architectural styles that are worth visiting. It is recommended to go around 2 pm and play until evening ~ ~ ~
Have a nice holiday.