Hi larrychen2330,
"Depending on your country or region, you might not be able to buy, download, or subscribe to certain types of media. The availability and features of certain apps, movies, and more can vary. "
You can find this information and helpful details here: Availability of Apple Media Services
Additionally, payment methods must match the region of the Apple ID or iCloud account.
"Before you update your location, you must spend your store credit, cancel your subscriptions, and get a payment method for your new country or region." Found here: Change your Apple ID country or region
If the payment method matches the Apple ID or iCloud account for purchases use the section "Use your computer to change your region" which is also quoted below.
"Use your computer to change your region
- Open the Music app or iTunes.
- In the menu bar at the top of the screen or the top of the iTunes window, click Account, then click View My Account.
- Sign in with your Apple ID.
- On the Account Information page, click Change Country or Region.
- Select your new country or region.
- Review the Terms & Conditions, then click Agree. Click Agree again to confirm.
- Enter your new payment information* and billing address, then click Continue.
You can also find helpful steps in the guide here: Change your country or region code in the App Store on Mac
And check your Media & Purchases settings with the steps here: Set up your Apple ID media and purchase settings on Mac
Cheers!
