What is the difference between email forwarding and an actual POP3 email account?
Basically, email forwarding just redirects an email written to your domain name (i.e. email@example.com) to a true email box/account (i.e. Johndoe@hotmail.com).
With a POP3 email account, the email sent to your domain name (i.e. firstname.lastname@example.org) will go into your domain name's in-box, allowing you to reply from the same email address.