create.php

<?php
    
    if (isset($_POST['submit']))
    {
        require "config.php";
        require "common.php";

        try {
            $connection = new PDO($dsn, $username, $password, $options);
                    
            $new_user = array(
                "firstname" => $_POST['firstname'],
                "lastname"  => $_POST['lastname'],
                "email"     => $_POST['email'],
                "age"       => $_POST['age'],
                "location"  => $_POST['location']
            );

            $sql = sprintf(
                "INSERT INTO %s (%s) values (%s)",
                "users",
                implode(", ", array_keys($new_user)),
                ":" . implode(", :", array_keys($new_user))
            );

            $statement = $connection->prepare($sql);
            $statement->execute($new_user);

        } catch(PDOException $error) {
            echo $sql . "<br>" . $error->getMessage();
        }
    } 
?>

<?php require "templates/header.php"; ?>

<?php 
    if (isset($_POST['submit']) && $statement) 
    { ?>
        <blockquote><?php echo $_POST['firstname']; ?> successfully added.</blockquote>
    <?php 
} ?>

<h2>Create a user</h2>

<form method="post">
    <label for="firstname">First Name</label>
    <input type="text" name="firstname" id="firstname">
    <br>
    <label for="lastname">Last Name</label>
    <input type="text" name="lastname" id="lastname">
    <br>
    <label for="lastname">Email</label>
    <input type="text" name="email" id="email">
    <br>
    <label for="lastname">Age</label>
    <input type="text" name="age" id="age">
    <br>
    <label for="lastname">Location</label>
    <input type="text" name="location" id="location">
    <br>
    <input type="submit" name="submit" value="Submit">
</form>

<a href="index.php">Back to home</a>

<?php require "templates/footer.php"; ?>