How can I make sure that the mail address in the form is real?

Hi All,

I’ve just bought NEX-Forms, but I am not sure how to make a mail address required blank, meanwhile to make sure the mail he inputs is a real email address, but not a fake one, especially, I would like to use her mail address to send the form result to me, any body knows how to make it?

Great Thanks!!!

Kurtis

https://wordpress.org/plugins/nex-forms-express-wp-form-builder/