can anyone please tell me how I can send email with freeBSD?

I guess the:

mail -s " subject" is for system internal mail only???

do i need to browse my for example ,,, login and then create the email from there? ..... or if there is a better way to send an email? thanks

FreeBSD, like most *nixs, requires a Mail Transfer Agent (MTA) to send external mail. On FreeBSD, sendmail is setup as the default MTA, so you should probably learn how to use that before trying out other MTAs. The FreeBSD handbook covers the configuration of sendmail fairly well: