Use message effects on Mac
With macOS 11 and later, you can add special effects to your messages — full-screen animations like fireworks, balloons or confetti; message-specific effects like a slam or echo; or interactive effects, like invisible ink that your friends need to swipe over to read your text.
In the Messages app on your Mac, select a conversation.
Enter your message in the field at the bottom of the window.
Click the Apps button , click the Message Effects button , then click an effect.
When you select an effect, you see a preview of it.
To send it, press Return on your keyboard or click the Send button .