HOW TO Edit, unsend, and more
1 Unsend a message
Both sender and receiver need to be using iOS 16, iPadOS 16, or macOS Ventura. Tap and hold on the message and choose Undo Send from the menu. The message will disappear from the thread on all devices.
2 Edit a message
As for Unsend, both parties need to be using a compatible version of Messages on iPhone, iPad, Watch or Mac. Tap and hold on the message until the menu appears, tap Edit, make changes and tap the blue checkmark.