Sent emails cannot be recalled
It’s not possible to recall an email that’s been sent in Yahoo Mail, saving a draft of your email lets you revisit and edit the content to make sure it’s perfectly worded.
When you begin composing an email Yahoo automatically saves it to your Drafts folder, located on the left hand side of your email. Revisit and edit it by clicking on the Drafts folder and selecting the email. Any changes remain saved there until you’re ready to send it.