<?php

    $DatabaseServer = "localhost";
    $DatabaseUsername = "root";
    $DatabasePassword = "root";
    $DatabaseName = "demo";

    $Connection = mysqli_connect($DatabaseServer, $DatabaseUsername, $DatabasePassword, $DatabaseName);

    if ($Connection === false) {
        die("ERROR: Could not connect. " . mysqli_connect_error());
    }

    $sqlusers = "select * from user";
    $result = mysqli_query($Connection, $sqlusers);
        echo "<form method='POST'>";
    while($rowuser = mysqli_fetch_array($result)){
        $user = $rowuser['FirstName'];


        echo "<input type='text' name='firstName' value='$user' readonly>";
        echo "<select name='attendanceType'>";

            $sqltype = "select * from attendancetype";
            $resultaType = mysqli_query($Connection, $sqltype);
            while($rowtype = mysqli_fetch_array($resultaType)){
                echo "<option>";
                echo $rowtype['name'];
                echo "</option>";
            }

        echo "</select>";
        echo "<br>";

    }
    echo "<input type='submit' name='submit' value='submit'>";
    echo "</form>";
    ?>

INSERT INTO `user` (`UserID`, `FirstName`, `LastName`, `Email`, `Password`, `City`) VALUES
(7, 'Rahul', 'Rajshekaran', 'Rahul@zzz.xxx', 'Rahul@123', 'Pune'),
(8, 'Mahesh', 'Krishna', 'Mahesh@xxx.xxx', 'Mahesh@123', 'Delhi');

INSERT INTO `attendancetype` (`attendanceTypeID`, `name`) VALUES
(0001, 'Present'),
(0002, 'Absent');

$i = 0;
while($rowuser = mysqli_fetch_array($result)){
    $user = $rowuser['FirstName'];


    echo "<input type='text' name='firstName[".$i."]' value='$user' readonly>";
    echo "<select name='attendanceType[".$i."]'>";

        $sqltype = "select * from attendancetype";
        $resultaType = mysqli_query($Connection, $sqltype);
        while($rowtype = mysqli_fetch_array($resultaType)){
            echo "<option>";
            echo $rowtype['name'];
            echo "</option>";
        }

    echo "</select>";
    echo "<br>";
    $i++;
}

<?php
foreach($_POST['firstName'] as $i => $user) {
  $sql = "insert into table set attendance_type = '".escapeFunction($_POST['attendanceType'][$i])."' where user='".escapeFunction($user)."'";
  mysql_query($Connection, $sql);
}
?>