How to sign in to iCloud on iPhone

To sign into your Apple Account follow these steps and iCloud features will be enabled automatically.

1. Open the Settings app.
2. Tap Apple Account at the top.

3 . Choose a method to sign in:

• • Use Another Apple Device: If you have another iPad or iPhone that’s signed in to your Apple Account, bring that device nearby and follow the instructions on both devices to complete sign-in.*
  • Sign in Manually: Enter your Apple Account email address or phone number and your password. If prompted, enter the six-digit verification code sent to your trusted device or phone number to complete sign-in.

If you can’t sign in to your Apple Account

• You can reset your password if you forgot your Apple Account password.
• Get suggestions on how to find the email address or phone number that you use with Apple Account.
• If you use two-factor authentication with your Apple Account, you also need a verification code to sign in.
• Learn what to do if you see a message that your Apple Account is locked, not active, or disabled.
• If you see a Sign in with Apple button on a participating third-party app or website, you can use your existing Apple Account to quickly set up an account for that third-party app or website and sign in. If you can’t sign in to a third-party app or website with your Apple Account, contact the developer.
• If you try to sign in on your device and it continuously spins or can’t connect to a server, check Apple’s system status page for an outage in your country or region. If there’s no outage, try connecting to another internet network or try again later.

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copied from: Sign in to your Apple Account on the web or in your device settings - Apple Support