Hi, I Just want process all xml files within multiple subfolders

But my current code is used to grep the files within the folder

use strict;
undef $/;
my $path = $ARGV[0];
my $out = $ARGV[1];

opendir(DIR, $path) || die "cannot read folder path";
my @xmlfiles = grep {/\.xml$/i} readdir(DIR);
closedir(DIR);

foreach my $xml(@xmlfiles) {
open(FIN, "$path/$xml") or die("Couldn't open input File!!");
my $file = <FIN>;
[download]

Can anyone knows how to process within multiple folders in perl