Insert Code
$tid = $_POST['tid'];
$email = $_POST['email'];
$password = $_POST['password'];
$confirm password = $_POST['confirm password'];


// please remove last ' , (coma)' from fileds

mysqli_query($conn,"INSERT INTO `admin` ( `tid`,`email`,`password`,`confirm password`, ) VALUES ('$tid','$email','$password','$confirm password',)");
Select Single
$getdata = mysqli_query($conn,"SELECT * FROM admin ");
$row = mysqli_fetch_array($getdata);
$tid = $row['tid'];
$email = $row['email'];
$password = $row['password'];
$confirm password = $row['confirm password'];
Select While
$getdata = mysqli_query($conn,"SELECT * FROM admin ");
while($row = mysqli_fetch_array($getdata)) {
$tid = $row['tid'];
$email = $row['email'];
$password = $row['password'];
$confirm password = $row['confirm password'];
}
Delete Code
$getid = $_GET['id'];
mysqli_query($conn,"DELETE FROM admin WHERE tid ='$id' ");
Update Single Code
$tid = $_POST['tid'];
$email = $_POST['email'];
$password = $_POST['password'];
$confirm password = $_POST['confirm password'];

mysqli_query($conn,"UPDATE `admin` SET `tid` = '$tid' WHERE `admin`.`tid` = 1")
mysqli_query($conn,"UPDATE `admin` SET `email` = '$email' WHERE `admin`.`tid` = 1")
mysqli_query($conn,"UPDATE `admin` SET `password` = '$password' WHERE `admin`.`tid` = 1")
mysqli_query($conn,"UPDATE `admin` SET `confirm password` = '$confirm password' WHERE `admin`.`tid` = 1")