On iPad, you control which of your contacts an app can access. The first time an app wants to access your contacts, you receive a request from the app, along with an explanation. For example, a messaging app may ask to access your contacts in order to find friends who are using the same app. After you grant or deny the app’s request, choose which contacts the app can access. You can always change the access you granted later.
Go to Settings Control access to information in apps on iPad