Your Substack writer email is an alias to the address on your Substack account which means when a subscriber replies to an email newsletter, you'll receive it in your inbox, just like a regular email.
All Substack posts are sent from an email address with the format [subdomain]@substack.com. At this time, there currently isn't an option to change or otherwise customize this address.
Tip: Only want to receive replies from your subscribers? View steps on how to change those settings here.