Shanghai hukou has 15 urban insurance, and the company that works now pays social security. How can we turn that 15 urban insurance into social security?

You are a foreign household registration, and you have paid enough social security 15 years in Shanghai, which is useful to the company;

Before the retirement age, you transfer the social security in Shanghai to the household registration, and if you don't do it in Shanghai, you transfer it to the household registration. When you retire, you can enjoy social security benefits at your domicile.

Further reading: How to buy insurance, which is good, and teach you how to avoid these "pits" of insurance.