UPDATE: You also cross-posted this question on Stackoverflow. It's good form to mention that and provide a link.

There are problems with your code. You should always use strict; at the top of all your code and let Perl find some of your errors for free.

But besides that you are using a module that doesn't return the data in the way you want. You should use Config::Tiny which is only for ini-style files, and returns a reference to a hash structure as you want:

#! perl -w
use strict;
use feature qw/ say /;

use Config::Tiny;
my $cfg = Config::Tiny->new;
   $cfg = Config::Tiny->read('new.conf') or die $!; 

foreach my $section (sort keys %{ $cfg }) {
  say "section: $section";
  foreach my $param (sort keys %{ $cfg->{ $section } }) {
    say "$section.$param : $cfg->{ $section }->{ $param }"; 
  }
}

__END__
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