Open Settings
Tap Safari
Tap Clear History and Website Data
Confirm by tapping Clear History and Data
Open Settings
Tap General
Tap iPhone Storage
Select an app
Tap Offload App to clear app cache while keeping documents and data
Tap Delete App to remove the app and its data
Reinstall the app from the App Store
Restart the iPhone
Update iOS to the latest version
Clear cache inside individual apps if the app provides that option