- View your Purchase History here:
View your purchase history for the App Store and other Apple media services - Apple Support
- View your subscriptions here:
View or cancel app subscriptions on iPhone - Apple Support
If you are the Organizer of a Family Plan, then you will have the option to view purchases made by family members on your account by choosing their Apple ID when viewing your Purchase History. For any purchase on your device, it requires double clicking the side button with the amount showing on the screen followed by verification with FaceID/TouchID or Passcode. It is not something that can be done by accident.
If you signed up for a free trial, that would need to be cancelled at least 24 hours before the trial period ends to avoid any charges. There is also the possibility that your card has been compromised by using it on a terminal that had a skimmer installed or by entering the actual account information online. That would need to be resolved by contacting the issuing bank of the card.
Post the 2 screenshots of the links above and we should be able to offer more specific instructions.