Open Messages for me
In the Messages app to the right of the To field. Click a contact in the list, then click the email address or phone number.
Send a message to more than one person: See Send audio clips in a text.
Emoji: Click the Emoji button Find a location in Maps.
To start a conversation, click Message in the Map Info screen or click a link from the email.
If this is the first time you’ve messaged this business, a new conversation is created. Otherwise, you can continue your conversation.
You can’t send a message to a business that’s How to use Business Chat.
You can forward a message (or an attachment such as a photo or video) from a conversation.
In the Messages app Apple Support article: Use Messages with your Mac