New iPad for shared account

If your devices are sharing a common AppleID for iCloud, you’ll encounter all kinds of issues with unintentional and/or unwanted sharing of sensitive/private information (including Messages). You’ll not be able to reliably maintain any kind of data separation.

The Golden Rule: Don’t share an AppleID between users. Each user should have their own AppleID for their own exclusive use - linked to their own primary email (and secondary/recovery email addresses and trusted telephone numbers). 

You would be best advised to separate your digital identities and configure a new AppleID for yourself or partner.

How to create a new Apple ID – Apple Support

After separating your identities, should you choose to do so, you can continue to selectively share purchased Apple Services, Subscriptions, Apps and Media using Apple’s Family Sharing features:

Family Sharing - Apple

Set up Family Sharing – Apple Support

Share App Store, iTunes Store and Apple Books purchases with Family Sharing – Apple Support

https://www.imore.com/how-set-up-family-sharing-iphone-ipad

Setting aside the above considerations, if you simply wish to copy/transfer existing setup and data, these support pages should get you started with setup of the new iPad - and the methods of transferring your data from old to new iPad:

Set up your iPhone, iPad or iPod touch – Apple Support

Transfer data from your previous iOS device to your new iPhone, iPad, or iPod touch - Apple Support

Use Quick Start to transfer data to a new iPhone, iPad or iPod touch – Apple Support

If the donor iPad, from which you are transferring your data precedes iOS12.4, QuickStart will not be available.

“Transfer” is rather a misnomer. In reality, your data and setup is merely cloned to the new device. Nothing is moved or removed from the original device.

An alternative is to restore either an iCloud or iTunes backup to the new device:

How to back up your iPhone, iPad and iPod touch – Apple Support

Restore your iPhone, iPad, or iPod touch from a backup - Apple Support

Assuming that you accept the implications of doing so, perhaps the easiest way to move all data and settings to your new iPad is to setup the new device using the original AppleID credentials - then perform the standard transfer or restore processes - and finally change the AppleID account.

This will transfer everything (inclusive of sensitive and personal data) to the new AppleID account - after which you will be able to manually delete information from the new iPad. After subsequent change to the new AppleID, your accounts will be fully independent - but you can continue to share information as required using iCloud sharing facilities.

Transfer

These support pages should get you started with setup of your new iPad - and the methods of transferring your data from old to new iPad:

Set up your iPhone, iPad or iPod touch – Apple Support

Transfer data from your previous iOS device to your new iPhone, iPad, or iPod touch - Apple Support

Use Quick Start to transfer data to a new iPhone, iPad or iPod touch – Apple Support

If the donor iPad, from which you are transferring your data precedes iOS12.4, QuickStart will not be available.

“Transfer” is rather a misnomer. In reality, your data and setup is merely cloned to the new device. Nothing is moved or removed from the original device.

An alternative is to restore either an iCloud or iTunes backup to the new device:

How to back up your iPhone, iPad and iPod touch – Apple Support

Restore your iPhone, iPad, or iPod touch from a backup - Apple Support

Apps are not directly transferred between devices. For Apps, the transfer process creates a record of the Apps that are installed on the donor iPad - and it is this record of installed Apps that is transferred to the target (new) device. For Apps that are still available for download from the App Store, the corresponding Apps are automatically downloaded and installed from the App Store.

Not all Apps will, necessarily, continue to be available. Apps may have been removed or retired from the App Store by the respective App Developer. Some Apps may have been abandoned - and may not be compatible with the new device. Where a compatible App is not available, you’ll not be able to transfer/install the App.

Change AppleID Account

If you do wish to change and use a different AppleID as recommended, first ensure that you have disabled the Activation Lock that will otherwise cause difficulties in the future. You can disable the Activation Lock by disabling the Find My service from iPad/iPhone settings before trying to use a different AppleID account:

Settings > [Your Name / AppleID] > Find My > Find My iPad - set to OFF

Having disabled the Activation lock, you can now sign-out from the original AppleID:

Settings > [Your Name / AppleID] > Sign Out

Presumably you’ll want to keep any iCloud data that is locally stored on your iPad. If so, accept the opportunity to keep a local copy of your data (e.g., Calendar, Contacts, Notes, Keychain Passwords etc.) - as otherwise this data will be wiped from your iPad as you sign-out from iCloud. 

Also ensure that you have signed-out from Messages and FaceTime:

• Settings > Messages > Send and Receive > [AppleID] - scroll to the bottom where you will find your signed-in AppleID highlighted in blue text; tap and select Sign Out

• Settings > FaceTime > [AppleID] - again, scroll down the page to find your signed-in AppleID highlighted in blue text; tap and select Sign Out

After signing out, a restart of your iPad is recommended:

Restart your iPad - Apple Support

After restarting, you can sign-in to your new AppleID account from iPad settings - and also sign-in to Messages and FaceTime if necessary. Any iCloud data that you saved to your device during the previous sign-out will be merged with the new AppleID account.