Open Outlook and go to the Sent Items folder
Double-click the email you want to recall to open it in a separate window
Go to the Message tab
Select Actions
Click Recall This Message
Choose Delete unread copies of this message or Delete unread copies and replace with a new message
Optionally, select Tell me if recall succeeds or fails for each recipient
Click OK
If replacing the message, edit and resend the updated email
Check the recall status notification if enabled
Note that recall works only in certain Microsoft Exchange or Microsoft 365 accounts and only if the recipient has not read the message