@Lazher YAAKOUBI Thanks for posting in our Q&A.
For iOS enrollment, there are 5 methods:
https://learn.microsoft.com/en-us/mem/intune/enrollment/device-enrollment#iosipados-enrollment-methods
And enrollment is divided as device enrollment and user enrollment. If we select "User enrollment" in Enrollment type, it will be known as user enrollment. If you don't configure or select "device enrollment", it will be known as device enrollment.
https://learn.microsoft.com/en-us/mem/intune/enrollment/ios-user-enrollment#create-a-user-enrollment-profile-in-intune
When we configure the restriction policy, we are needed to know what method we used to enroll the iOS.
Hope it will address your confusion.
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