Of course, you can have @ gmail.com or @ wp.pl mailboxes. However, when you are serious about developing your website, nothing looks more professional than having an email address from your domain.
Well, here we come to the point. To be able to use an e-mail address on WEBD.pl hosting, you need to purchase a hosting account package (all types of WEBD.pl accounts offer e-mail accounts included in the price) and your own domain. This domain is the address of both your website and your e-mail address (it will appear after the @ sign).