Share iCloud storage iPad/iphone

Aah, OK, thank you for sharing that.

FYI: You cannot merge multiple Apple ID, i.e. apps, music and others, you cannot transfer from one account to another.

1.

👉 I don't know what you want to do with your iPhone Apple ID, read the following carefully:

Understand and control the personal information that you store with Apple

Understand and control the personal information that you store with Apple - Apple Support

Read carefully -> How to delete your Apple ID account

How to delete your Apple ID account – Apple Support (UK)

How to deactivate your Apple ID account

How to deactivate your Apple ID account – Apple Support (UK)

Scroll to ->  How to temporarily deactivate your Apple ID

Sign in to your Apple ID account page on a Mac, PC, iPhone, or iPad. Then scroll down to Data and Privacy, and select "Manage your Data and Privacy." On the following page, select "Get started" under "Deactivate your account." If you don’t see this option, it means that this feature is not available in your country or region. 

👉 When you request to deactivate your account, you receive a unique alphanumeric access code. Make sure that you keep this access code in a safe place—you must have it to reactivate your account. 

If you forgot the access code, try to contact Apple Support -> Get Support (apple.com)

how do I change my ID on the iPhone?

2.

👉 See this Apple article: Change your Apple ID

Change your Apple ID - Apple Support (SG)

Then see this Apple article: What to do after you change your Apple ID or password

What to do after you change your Apple ID or password - Apple Support

If you use the same Apple ID then on both devices must have the iCloud+.

Check -> Go to -> Settings -> your name -> iCloud -> if you see 50 GB (or 200 GB ot 2 TB).

If you have an iCloud subscription, you will receive a monthly bill from Apple, check your e-mail box.

You pay monthly for iCloud storage. 

Use the same Apple ID on iPad and iPhone.