Updating database table through a textarea

I'm creating a simple website with just two or three pages, and I'm using Froala editor to edit the content directly from the page. So I have a <textarea> within a form with the id of "edit" (To make it a wysiwyg editor) and a submit button. So basically what I want it to do is to UPDATE the "body" column in the table "pages" (where the type = 1) in my database when the button is submitted... Here's the code I have:

<?php

    $query = "SELECT * FROM pages WHERE type = 1";
    $result = mysqli_query($dbc, $query);

    $page = mysqli_fetch_assoc($result);

?>

And the html:

<form>
    <textarea id="edit" name="body"><?php echo $page["body"]; ?></textarea>
    <button type="submit" class="button button-primary">Save</button>
</form>