How do I send Blind copies to many email recipients?

In your post you have asked - How do I send blind copies to many email recipients and see blind copies of mails also .

See these articles Address emails in Mail on Mac - Apple Support

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If I send out a Christmas card to many, I usually send it to myself (TO field) and then put all 30 addresses in the BCC field - that way, no one knows or has to scroll through all of those addresses - they just see mine and theirs.

On the new message window, select the BCC address field from the Lists button.