Gmails Undo Send function allows you to develop a grace duration on your own. You can set it to provide yourself up to 30 seconds to undo the sending out of an e-mail. I have it enabled in all of my individual and professional Gmail accounts including my school G Suite for Edu account..
View this short video to learn how to allow “undo send out” in your Gmail account..

Have you ever struck “send out” a bit too quickly when writing an e-mail? Have you ever inadvertently sent an e-mail to the wrong person or accidentally hit “reply all” when you only needed to respond to someone? If so, you should think about making it possible for Gmails “Undo Send” function..