如何将表单内容发送到电子邮件？使用Html和PHP

我已经创建了一个表单，希望在有人单击“提交”按钮时将表单内容提交到我的电子邮件中

以下代码是以form.html格式编写的

我不能让它工作。我尝试在一个.php文件中编写html部分，但当我这样做时，整个页面以代码的形式打开

我试图查找如何将表单信息提交到电子邮件地址，但找不到任何内容。我感谢所有的帮助

HTML

班级
辅导
重置
提交

PHP代码 我试图编写以下代码来使用我从网站表单收到的电子邮件

<?php

if (isset($_POST['submit'])) {
    $FirstName = $_POST['FirstName'];
    $LastName = $_POST['LastName'];
    $Company = $_POST['Company'];
    $Email = $_POST['Email'];
    $Classes= $_POST['Classes'];
    $Tutoring= $_POST['Tutoring'];

    $mailTo = "testemail@gmail";
    $headers = "From: ".$Email;
    $txt = "You have received an e-mail from ".$FirstName.".\n ".$LastName ".$Company
    ".$classes".$tutoring;

    mail($Email, $txt, $headers);
    header("Location: contactus.html?mailsend");
}

<?php

if (isset($_POST['submit'])) {
    $FirstName = $_POST['FirstName'];
    $LastName = $_POST['LastName'];
    $Company = $_POST['Company'];
    $Email = $_POST['Email'];
    $Classes= $_POST['Classes'];
    $Tutoring= $_POST['Tutoring'];

    $mailTo = "testemail@gmail";
    $headers = "From: ".$Email;
    $txt = "You have received an e-mail from ".$FirstName.".\n ".$LastName ".$Company
    ".$classes".$tutoring;

    mail($Email, $txt, $headers);
    header("Location: contactus.html?mailsend");
}