Ok, that's a better question. Still no code, but maybe this will get you started:

use warnings;
use strict;
use Algorithm::Loops qw(NextPermute);

my $number = '123';
my @digits = split //, $number;
my @array = ($number); # Add the first permutation

push @array, join '', @digits while NextPermute (@digits);

print "@array";
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Prints:

123 132 213 231 312 321
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