Hello !!!

My directory D:\conv\ESSD\YJCIS\YJCIS14183\bbb.doc

I must send to X:\sgml_db\ESSD\YJCIS\YJCIS14183\
directory and rename bbb.doc to MMC1.doc.
If X:\sgml_db\...\....\YJCIS14183\ don't exist, i must create it.

"X:\sgml_db\" constant directory.

My script must choose path itself !
What I must add to this script !!!

use strict;
use warnings;
use File::Copy;
use File::Path;

my $sDest = 'X:/whatever';
mkpath $sDest;
copy('D:/whatever/bbb.doc', qq{$sDest/MMC1.doc});

Try reversing those / to \ or using two if that doesn't work:
D:\whatever\bbb.doc or
D:\\whatever\\bbb.doc or

The first \ is ignored and tells the interpreter to accept what comes next as OK.