UK Apple ID

Hello there, rsshea.

It sounds like you are wanting to change your country store to the UK store for the purpose of using the Game Pass application. The following Knowledge Base article offers the steps on how to accomplish that:

Change your iTunes Store country or region

What you need know before you change your country or region

When you change your iTunes Store country:

• Update your billing address to one in your new country. When you change your billing address, the primary address for your Apple ID and your other Apple services, such as the App Store and iCloud, automatically updates.
• You might need to update your payment method. For example, only German credit cards can be used to buy content from the German iTunes Store and App Store.
• You won't see the items that you purchased from the previous country’s store in your Purchased section.
• You won’t see the items from your iCloud Music Library that you matched, uploaded, or added from the previous country’s store.

When you make a purchase in the iTunes Store, App Store, iBooks Store, or Mac App Store, the country in your iTunes Store account information must match the country listed on your Apple ID account page.

Find out what to do if you can't change your country or region.

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Change your country

On your iPhone, iPad, or iPod touch

1. On your device, tap Settings > iTunes & App Store.
2. Tap your Apple ID.
   If you're not signed in, sign in with the Apple ID and password that you use with the iTunes Store.
3. Tap View Apple ID.
   
4. If prompted, enter your password again.
5. Tap Country/Region. Learn what to do if you can't change your country.
6. Tap Change Country or Region.
7. Tap your new country, then tap Next.
8. Review the Terms and Conditions and Apple Privacy Policy, then tap Agree if you agree to the terms and conditions.
9. In the prompt that appears, tap Agree.
10. Select a payment method and enter your payment information. Learn more about how to change or remove your Apple ID payment information.
11. Enter your billing address and tap Next.

Your Apple ID country updates for all of your Apple services on all of your Apple products.

Thanks for reaching out to Apple Support Communities.

Cheers.