Good morning, I am having problems using dbquery to query my database,

When I run the following code:

select(‘*’);

$sql->from(‘ps_orders’, ‘o’);

print($results = Db::getInstance()->executeS($sql));

?>

I get a 500 error from the server, I don’t know if this is because the server is rejecting the SQL connection or I am doing something wrong in the code.

I’ve searched many forums but I don’t know what I’m doing wrong.