db_value_enter.php

<?php require 'php database connection.php'; ?>
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <form action="" method="POST">
    <table>
<tr>
    <td>Name</td>
    <td><input type="text" name="e_name" require></td>
</tr>
<tr>
    <td>Email</td>
    <td><input type="email" name="e_email" require></td>
</tr>
<tr>
    <td>Phone</td>
    <td><input type="tel" name="e_phone" require></td>
</tr>
<tr>
    <td></td>
    <td><input type="submit" name="e_add" require></td>
</tr>
    </table>
    </form>
    <?php
    if(isset($_POST['e_add']))
    {
        $e_name = $_POST['e_name'];
        $e_email = $_POST['e_email'];
        $e_phone = $_POST['e_phone'];

        $sql = "INSERT INTO employee (e_name,e_email,e_phone) VALUES ('$e_name','$e_email','$e_phone' )";

        if(mysqli_query($conn,$sql))
        {
            echo "<script> alert ('Wow record created sucessfully');</script>";
        }
        else
        {
            echo "ERROR:" ,$sql . "<br/>", mysqli_error($conn);
        }
    }
    ?>
</body>
</html>