#!perl
use strict;
use warnings;

use Mojo::UserAgent;

my $ua = Mojo::UserAgent->new( 'insecure' => '1' );
my $tx = $ua->build_tx(
    'POST' => 'https://my.webpage.com/my/path',
    {
        'Accept'         => '*/*',
        'User-Agent'     => 'curl/7.55.1',
        'Content-Length' => '15',
        'Content-Type'   => 'application/x-www-form-urlencoded',
        'My-Header'      => 'alfa',
        'My-Header-2'    => 'beta'
    },
    "here is my data"
);
my $res = $ua->start($tx)->result;



__END__

Created from curl command line
curl -kv -X POST
    "https://my.webpage.com/my/path"
    --header 'My-Header: alfa'
    --header 'My-Header-2: beta'
    --data-raw 'here is my data'