The default national currency of the account is New Taiwan Dollar, and the foreign currency U.S. dollar currency has been added,

Hey there, userlilu. Thanks for reaching out to the Community.

Can you please let me know the details of what you're trying to achieve regarding the currencies on your account? Any additional details you can provide me will help to ensure a timely solution.
 

Meanwhile, I've got you some articles that contain information about Multi-currency for your reference:

• About Multicurrency
• Frequently Asked Questions about Home Currency Adjustments
• Turn on and use multicurrency

Looking forward to helping you regarding currency concerns or any other QuickBooks realted questions.