<?php
header('Content-Type: text/html; charset=UTF-8');

$clantag = "<#CLANTAG>"; // #Clantag (capital letters)

$token = "<TOKEN>";
$url = "https://api.clashroyale.com/v1/clans/" . urlencode($clantag);

$ch = curl_init($url);

$headr = array();
$headr[] = "Accept: application/json";
$headr[] = "Authorization: Bearer ".$token;

curl_setopt($ch, CURLOPT_HTTPHEADER, $headr);
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);

$res = curl_exec($ch);
$data = json_decode($res, true);
curl_close($ch);

echo "<pre>";
print_r($data);
echo "</pre>";
?>