how to create apple id in iphone 4

See How to create a new Apple ID https://support.apple.com/en-us/HT204316and

How to switch Apple IDs on your iPhone or iPad

https://www.imore.com/how-change-apple-id-your-iphone-or-ipad

See the data implications below.

Some of these things may apply even though not changing an Apple ID: What to do after you change your Apple ID or password https://support.apple.com/en-us/HT204071

 Keep in mind that some things available under a first Apple ID will not be available under a new Apple ID. For example, you won’t be able to transfer anything purchased from the App and iTunes Stores to the new ID. And, there are other issues to be addressed.

And see what Eric Root says on this matter here  https://discussions.apple.com/thread/251483565and

what Winston Churchill says about it here: https://discussions.apple.com/thread/7452747

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You also can set up family sharing between the IDs to share purchases made with them. See:

Family Sharing  https://support.apple.com/en-us/HT201060

Set up Family Sharing https://support.apple.com/en-us/HT201088

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But if you only want to Change your Apple ID https://support.apple.com/en-us/HT202667. 

And see What to do after you change your Apple ID or 

Password https://support.apple.com/en-us/HT204071 (supplementary to what the fist link says)

And FYI, see  iCloud: About your @icloud.com, @me.com, and @mac.com email addresses  https://support.apple.com/en-us/HT201771

Post back if you have questions about what you can do if your Apple ID (1) is a third-party apple ID or (2) ends in icloud.com, me.com, or mac.com. 

Are you getting an error message when trying to create a new ID? Something like the maximum number of free accounts has been created?

Create a new ID (if necessary) and sign into iCloud using the same Apple ID on another Apple device/computer. You should then be able to sign in.

iCloud: The maximum number of free accounts have been activated.   

Or contact Apple ID Support.  See the Apple Support articles below for contact information.  

Apple ID - Official Apple Support.    

Contact Apple for help with Apple ID account security - Apple Support.   (Link doesn’t always load)  

Get Support          Work through the screens to get a chat option. You may have to pick a slightly different problem.

Apple Support schedule phone call

https://twitter.com/AppleSupport.          People have posted it may take an hour or more to get a response.

Perhaps this may help: https://support.apple.com/en-us/HT204316

You can also create an AppleID on any web browser by going to https://appleid.apple.com