You control whether third-party apps have access to information in Contacts, Photos, Calendar, and other apps.
The first time an app wants to use information from another app, you receive a request with an explanation. For example, a messaging app may request access to your contacts to find friends who are using the same app. After you grant or deny access, you can change access later.
Go to Settings Apple Support article: About App Privacy ReportApple Support article: About privacy and Location Services