My sons share my apple ID, I no longer want to have access to there information. How do I create a new apple id for them and not lose any of their information

1. Wipe the iPhone: What to do before you sell, give away, or trade in your iPhone, iPad, or iPod touch - Apple Support
2. Create a new Apple ID using a valid 3rd party email address (Gmail, Yahoo, etc...) not use in an Apple environment: How to create a new Apple ID - Apple Support
3. Setup Family Sharing to share books, apps and music purchases: Set up Family Sharing - Apple Support

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. Also set up Family Sharing to keep access to your apps/purchases. 

How to transfer all files from one iCloud account to another

 Apple ID email address or password - What to do after you change