keep always logged in using php

this is my code and I want that user stay logged in until he log out from website,

<?php 
session_start();
include_once "config.php";
$email = mysqli_real_escape_string($conn, $_POST['email']);
$password = mysqli_real_escape_string($conn, $_POST['password']);
if(!empty($email) && !empty($password)){
    $sql = mysqli_query($conn, "SELECT * FROM users WHERE email = '{$email}'");
    if(mysqli_num_rows($sql) > 0){
        $row = mysqli_fetch_assoc($sql);
        $user_pass = md5($password);
        $enc_pass = $row['password'];
        if($user_pass === $enc_pass){
            $status = "Active now";
            $sql2 = mysqli_query($conn, "UPDATE users SET status = '{$status}' WHERE unique_id = {$row['unique_id']}");
            if($sql2){
                $_SESSION['unique_id'] = $row['unique_id'];
    
                echo "success";
            }else{
                echo "Something went wrong. Please try again!";
            }
        }else{
            echo "Email or Password is Incorrect!";
        }
    }else{
        echo "$email - This email not Exist!";
    }
}else{
    echo "All input fields are required!";
}

?>

I want that user stay logged in after closing the browser.