Change password plugin roundcube

Operating system: Ubuntu
OS version: 18.04

Hello there,
I have a problem enabling that feature in my Virtualmin users
I already installed Roundcube on one subdomain for all users

but when I do that step
/* INSTALLING:
gcc -o chgvirtualminpasswd chgvirtualminpasswd.c
chown root.apache chgvirtualminpasswd
strip chgvirtualminpasswd
chmod 4550 chgvirtualminpasswd
*/

I got that message:
gcc: error: chown: No such file or directory
gcc: error: root.apache: No such file or directory
gcc: error: strip: No such file or directory
gcc: error: chmod: No such file or directory
gcc: error: 4550: No such file or directory
gcc: fatal error: input file ‘chgvirtualminpasswd’ is the same as output file
compilation terminated.

how can I solve it?