#Php
$clickid =$_GET["clickid"];
$sub1=$_GET["sub1"];
echo "clickid = ".$clickid;
echo "sub1 = ".$sub1;

// JS
var url = new URL("https://testurl.net/test.php?clickid=asd54a5s6d&sub1=asd45a6sd4")

console.log("clickid",url.searchParams.get("clickid"))
console.log("sub1",url.searchParams.get("sub1"))