iCloud: Answer or forward emails in iCloud Mail
You can reply to or forward messages using Mail on iCloud.com.
Reply to or forward an email
To reply to the message you’re reading: Click the Reply button, then choose Reply or Reply All.
Choosing Reply All sends your response to the sender and all of the original recipients of the message.
To forward a message to one or more recipients: Select the message in your message list, click the Reply button in the toolbar, choose Forward, then type the email addresses.
You can also choose Forward as Attachment to have the original message attached as an EML file to the new message.
Include original attachments
You can include original attachments when replying to a message or forwarding it to a new recipient.
Click the Action pop-up menu in the sidebar, then choose Preferences.
Select “Include original attachments in reply,” then click Done.