I tried the above and it did not seem to work. But I modified it slightly according to code I had written in Java, and it works. It uses v7 of the Bing API. Here is my slightly modified code below.

#!/usr/bin/perl

use strict;
use warnings;
use LWP::UserAgent;
use JSON;

my $bing_key="PUT_YOUR_KEY_HERE";
my $query = "Hello";

{
    my $href = "https://api.cognitive.microsoft.com/bing/v7.0/search?q
+=$query&Accept=application%2Fjson&offset=0&count=10&subscription-key=
+$bing_key";
    
    print "Connecting to Bing for: $href\n";
    my $ua= LWP::UserAgent->new();

    my $req = HTTP::Request->new(GET => $href);

    print "-- \$href=$href\n";
    $req->header('content-type' => 'application/json');
    
    my $res = $ua->request($req);
    print $res->as_string;
    
  # Check the outcome of the response
  if ($res->is_success) {
    print "I could connect to the API\n";
     my $resp= $ua->get($href);
    my $data = decode_json($resp->content); 
    my @urls = map { $_->{'Url'} } @{ $data->{d}->{results} };
  }
  else {
    print "Impossible retrieving info from Web\n";
  }
}

1;
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