Send a group message
Open Messages and tap to start a new conversation, then enter the recipients' names or tap to pick from your contacts.
If group messages that are sent as MMS appear as individual texts, you might need to turn on Group Messages in Settings > Messages. With group messages, there are no read receipts.
Add or remove someone from a group iMessage conversation
Anyone in the group message can add or remove someone from the conversation. To add a person to a group message, tap Details, then tap Add Contact.
You can remove a person from a group message that has at least four people. Tap Details, then swipe from right to left on the name of the person you want to remove. Then tap Delete.
Leave a group iMessage conversation
To leave a conversation, tap Details, then tap Leave this Conversation. If you don't see Leave this Conversation on your iOS device, get the latest version of iOS. If someone in the group isn't using iMessage or an iOS device, they might not be able to leave the conversation.
If you don’t want to leave a conversation, you can mute it. Open the Messages app and tap a conversation. Tap Details, then turn on Do Not Disturb. This will stop notifications from only the Group message, not your device. You'll still get the messages in the Messages app, and you'll still see notifications on your lock screen.