I don't know what your real purpose is, if it is to create this directly in PHP or not, but maybe the code below will help you, I created a variable that will store the website URL that will pass the $cat
variable as a parameter, to see the result I used the <a>
tag in html
The code would look like this:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<?php
$cat = 'Pathname';
$link = "https://yourwebsite.com/?s=cqs3&importo_desiderato=5000&categoria_cqs=' . $cat . '";
?>
<a href="<?php echo $link; ?>">5.000€</a>
</body>
</html>
If you want to get the result only in PHP, use the following code:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<?php
$cat = 'Pathname';
$link = "<a href='/?s=cqs3&importo_desiderato=5000&categoria_cqs=" . $cat . "'>5.000€</a>";
echo $link;
?>
</body>
</html>
Edit
You say that your code works only using HTML and not in PHP. Well, I've been analyzing it here and I saw that this was happening due to the fact that the file is in a directory, right? PHP was not understanding that the URL was from this directory, at least for me the error was this one in addition to the quotes
Please try the code below, I believe it will work in both PHP and HTML
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<?php
$cat = $_GET['categoria_cqs'];
$link = '<a href="/?s=cqs3&importo_desiderato=5000&categoria_cqs=' . $cat . '">5.000€</a>';
echo $link;
?>
<a href="/?s=cqs3&importo_desiderato=5000&categoria_cqs=<?php echo $cat; ?>">5.000€</a>
</body>
</html>