hi , i want to go from Hongqiao station to Shanghai Greenland Jiulong Hotel , by metro

Take line 10, get off at Hailun Road, Exit 2. Then walk southeast around 0.6 miles (1 kilometers) to arrive at the hotel. The duration is 45 mins and the ticket fare is CNY 5 per person.

Thanks but that line10 is two lines , how to choose correct one?

Yes, I understand what you said.
First of all, you don't need to get off and transfer to another one in the halfway.
Then you are advised to pay much attention to he electronic screen before getting on the the train.
In general, English voice prompt and the screen will show the destination. So don't worry.