There are three ways to let people that visit your site contact you. Here they are in increasing complexity.
An email address in the site's footer, header, and/or other page. I.e. "For questions/comments, contact email@example.com." This is often the best bet.
An email form that people can fill out on the site. It includes space for 1. a return address, 2. a subject and 3. a body message. Emails are delivered privately to your "firstname.lastname@example.org" inbox just like any other email would be.
A comments form that people can fill out on the site. It includes space for 1. a return address and 2. a body message. Comments appear publicly on the site for anyone to read, and you can moderate those comments (edit, delete).
Which is your preference?