Turn on Messages in iCloud on your iPhone, iPad, or Mac
Sign in with the same Apple ID on all devices
On iPhone or iPad, go to Settings
Tap your name
Tap iCloud
Tap Messages
Turn on Use on this iPhone or Sync this iPhone
On Mac, open Messages
Go to Messages
Click Settings or Preferences
Click iMessage
Turn on Messages in iCloud
Open the Messages app on a synced Apple device to view your messages
Use iCloud.com only if your messages are available through a synced device or backup access method
Restore a device from an iCloud backup to access older messages if needed