how to install rpm file in debian.i downloaded vsftpd.rpm to install ftp server

This really isn't a Perl related question.. now isn't it?

It would be nice if you monks could help me in this matter

Nice and appropriate are often two different things. Why don't you try joining the Linux mailing list (one of many) over on Yahoo Groups or post to one of the Linux related newsgroups. I'm sure you'll find someone to help you there.