By default, all .php files are executed as PHP code. If that doesn’t happen for your site, then most likely you have some .htaccess rules somewhere that change this behavior.
I checked your .htaccess file, and I see this line is present:
AddHandler application/x-httpd-php5 .php .html
If I comment out this line, the the views/index.php line gets executed as PHP (as it should). Without it, the PHP code is sent to the browser instead.
The default settings of the server are good for almost all cases. So I would suggest removing all the AddHandler and AddType rules everywhere, because in my experience they tend to cause more problems than solve them.
It should work without the AddHandler in PHP 5.6 too. And if your website can run on PHP 7.4, you definitely should, because PHP 5.6 is old and insecure. In general, you should always use the latest stable version of PHP if you can.