What does Apple have for you? If you really want to know, you can get answers on Apple's privacy website.
The site was launched in May in the European Union for compliance with GDPR and is now available in the US, Canada, Australia and New Zealand. It shows Apple customers how much data they have stored with Apple (calendars, photos, and documents), their purchase and usage history in the App Store, their support history with AppleCare, and other information.
So you can see and download your information from Apple.