#!usr/bin/perl

use feature qw/say/;

$hash = {
  'testing' => {
    'link' => "http://www.espn.com",
    'bandwidth' => "100",
    'r' => "2",
  },
};

die "'testing' not found!" unless($hash->{'testing'});

say $hash->{'testing'}->{'link'} // (die "'link' not found!");
say $hash->{'testing'}->{'bandwidth'} // (die "'bandwidth not found!");