Fiancé, son & I share an Apple ID

When changing to the new ID, there may be some data loss, but you can minimize it. If syncing photos with iCloud, ensure Optimization is turned off in Settings/Your Name/iCloud/Photos and/or in Photos/Preferences/iCloud. Then make sure full resolution photos are on the device/computer. When signing out of iCloud, if asked whether you want to retain data, choose yes. Messages conversations will be lost if they are addressed to the ID. See the article below for other places that the old ID should be removed. See Winston Churchill's response in the below discussion. If possible, also set up Family Sharing  between the IDs to keep access to your apps/purchases. 

 How to switch Apple IDs on your iPhone or iPad.      

How to transfer all files from one iCloud account to another.       

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

Family Sharing.         

Family Sharing - Set up.     

You should ideally each have your own Apple ID. Having an Apple ID is how Apple identifies you as an individual. If you share an ID then Apple thinks you are the same person.

Click here to see how to 'Create an Apple ID'. --> https://support.apple.com/HT204316

Apple ID Frequently Asked Questions - https://appleid.apple.com/faq/#!&page=faq

As the twin “Level 10 Pros” have posted, it’s best to NOT use a common AppleID amongst individuals.

While splitting them out can be a bit of a pain …

… it will only get MUCH harder the longer you wait; as more services are added and as security continues to “tighten-up.”

Apple’s maturing “sharing” capabilities have virtually eliminated all prior rationale to use a common AppleID.

Ladybuglover1130 wrote:

How can I fix this do we are not sharing call history

Just to clarify, the only way to fix this is to stop sharing an Apple ID. The posts above explain more about how to stop doing that.