To get 8 random numbers from the list, I used random. It requires 5.10 though...

#!/usr/bin/perl

use 5.010;
use strict;
use warnings;
use random qw(integer);
use Data::Dumper::Concise;

my @array = (4 .. 20);
for (0 .. 7) {
    my $array = 4 + rand 20;
    print Dumper($array);
}
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