I'm new to web dev and I'm trying to run a simple html form that redirects to a thank you message on a php page. However, nothing I do seems to work. I always get an error of page not working (http error 405). If I refresh the page it starts downloading. I'm using the live server extension and I have PHP installed.
HTML file:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
<link rel = "stylesheet" type = "text/css" href = "styles-signup.css">
<script type = "text/javascript" src = "script-signup.js"></script>
</head>
<body>
<div>
<h1 class = "title"></h1>
</div>
<div class = "form">
<h1 id = "header">Create Your Account</h1>
<form method = "POST" id = "signup" action = "action.php">
<input name = "firstName" type = "text" placeholder="First Name" required id = "fname">
<input name = "lastName" type = "text" placeholder = "Last Name" required id = "lname">
<input name = "Email" type = "email" placeholder="email, e.g. person@gmail.com" required id = "mail">
<input name = "newPassword" type = "password" id = "password" placeholder="Password" required minlength="8" maxlength="25">
<input name = "passwordConfirm" type = "password" placeholder = "Confirm Password" required minlength="8" maxlength="25" id = "cpassword">
<br>
<input name = "gender" type = "radio" id = "male" required>
<label for = "gender" id = "mlabel">Male</label>
<input name = "gender" type = "radio" id = "female" required>
<label for = "gender" id = "flabel">Female</label>
<input name = "gender" type = "radio" id = "other" required>
<label for = "gender" id = "olabel">Other</label>
<br>
<br>
<input name = "birthdate" type = "number" min = "1920" max = "2019" placeholder="Year Of Birth" id = bd required>
<br>
<input name = "terms" type ="checkbox" id = "box" required>
<p id = "tc">I agree to the <a href = "termsandconditions.txt" id = "tcLink">Terms and Conditions</a></p>
<input name = "submit" type = "Submit" id = "button" value = "Sign up">
<a href = "login.html" id = "login">Already have an account? Log in</a>
</form>
</div>
</body>
</html>
PHP File:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
</head>
<body>
<?php
echo "<p>Hi</p>";
?>
</body>
</html>