<?include "conninfo.php";

$id=$_POST["theid"];

$query="SELECT * FROM people WHERE id=$id";
$result=mysqli_query($link,$query);
$r=mysqli_fetch_array($result);

?>
Edit record:<br><br>

<form action="doedit.php" method="post">
First name: <input type="text" name="fn" value="<?echo $r["firstname"];?>"><br>

Surname: <input type="text" name="sn" value="<?echo $r["surname"];?>"><br>

Fav food: <input type="text" name="ff" value="<?echo $r["favfood"];?>"><br><br>

<input type="hidden" name="theid" value="<?echo $id;?>">

<input type="submit" value="Do edit"><br>
</form>