Open the Settings app
Tap Privacy & Security
Tap Clear History
Confirm by tapping Clear History
To clear Safari website data:
Open Settings
Tap Safari
Tap Clear History and Website Data
Confirm by tapping Clear History and Data
To clear Safari downloads list:
Open Safari
Tap the Bookmarks icon
Tap Downloads
Delete items (or use Settings > Safari > Clear History and Website Data)
To clear app-specific search/history:
Open the app
Go to Settings or History
Select Clear History or Delete Search History
To clear Messages conversation history:
Open Messages
Open a conversation
Tap and hold a message (or use Edit)
Delete the message(s) or the conversation
To clear call history:
Open Phone
Tap Recents
Tap Edit
Select calls to delete
Tap Delete
To clear keyboard/auto-fill suggestions:
Open Settings
Tap General
Tap Transfer or Reset iPhone
Tap Reset
Tap Reset Keyboard Dictionary