To search for contacts and content in conversations, click in the Search field in the top-left corner and enter what you’re looking for. Or, choose from the suggested contacts, links, photos, and more.
To view photos and videos, do one of the following:
View in the conversation: View the photo, play the video, or double-click the file to open it in a Quick Look window.
Note: Live Photos have a Live Photo button in the message.
After you listen to the message, it’s removed from the conversation in 2 minutes. To save it in the conversation, click Keep.
If someone shares a note from the Notes app
With macOS Big Sur or later or an iOS or iPadOS device, any type of item (such as a text message or video) can be sent blurred with invisible ink. Other message effects like bubble animation (such as Slam Effect) or screen animation (such as fireworks) are visible on macOS Big Sur or later; however, friends who don’t have it just see text, such as “sent with Slam Effect.”
In the Messages app What is Screen Time on Mac?iPhone Manuals website