Depends on how much you want to change. There are many outlets in Euro. You can go to the nearest bank and ask them if they have any. If so, you can change your ID card and fill out the form on the spot. The exchange amount per person per year cannot exceed the equivalent currency of $50,000. Probably no more than 38,000 euros. If you change more, please ask someone to bring your ID card to help you change it, and make an appointment, because the bank doesn't have that much inventory. If you change too much, you may need to apply to SAFE. The general cash limit for travel and study is basically no problem, and there is no need to apply separately. It is better to pay tuition in cash than in cash. If you really want to change cash, you'd better bring the documents to apply for tuition.

For Chengdu, it is recommended to go to China Bank in Rome (business department of Sichuan Branch) or Wuhou Sub-branch of China Bank (Zhu Xiaotian Scenic Area Street). These two places have the largest foreign exchange stocks in Chengdu, and basically all currencies have some stocks, so the chances of other outlets being exchanged are too small.

Besides, it depends on your purpose. The prices of cash and cash are different. If it is to be cost-effective, it must be the current exchange rate.