How to reply to submitter email adress? Here is example on how to do so but please be aware to use following solution at your own risk because your email might end up in spam folder.
BreezingForms is using Joomla Mail API to send email. Long ago we had option when users submits the form, Administrator of the form would get email from that user (with actual email address from submitter in FROM filed). That's no longer available as a solution due the high possibility that users will got emails as SPAMS. Since we had a lot of complaints on it we had to change functionality a bit so we added Reply-to field in Admin emails. When email is sent it's always sent from Joomla site (the email you specified in Joomla Global Configuration -> Server Tab -> Mail Settings).
To be able to answer to user who submitted your form you can set, for example, this shortcode {email} into Reply-to field. Note that you need to have exact element in form with name "email". On that way you will be able to reply him when you receive your email.
If you want to mask your email address you can use this shortcode see THIS documentation article.
To set old email sending behavior, open this file
administrator/components/com_breezingforms/libraries/crosstec/functions/helpers.php find line 374 and change code below:
$mail->setSender( array( $prev_from, $fromname ? $fromname : $_fromname ) );
change to:
$mail->setSender( array( $from ? $from : $prev_from, $fromname ? $fromname : $_fromname ) );
This way Admin received email will have email address of submitter in FROM field.
Once again, use this solution at your own risk because your email might end up in spam folder.