yes, u can . simply use mail() function if u want to use the default smtp host or you can add some code to connect to remote smtp server(such as gmail) etc...
I want to create a mailbox not send mail. I know that you can use mail() to send mail. Is there a way to create a mailbox? That is where email is the new mailbox.
There was an easy way out if your host is using cPanel - you would just access the script that does that for you. Don't remember the details, but I'm sure you can google it if that's your case.