You should give the input expecting a first name a name attribute. PS I would have chosen first-name.
Hello. Let me ask you a question, where and how I should put a name attribute?
Your code so far
<!-- file: index.html -->
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Registration Form</title>
<link rel="stylesheet" href="styles.css" />
</head>
<body>
<h1>Registration Form</h1>
<p>Please fill out this form with the required information</p>
<form method="post" action='https://register-demo.freecodecamp.org'>
<!-- User Editable Region -->
<fieldset>
<label for="first-name">Enter Your First Name: <input id="first-name" type="text" required /></label>
<label for="last-name">Enter Your Last Name: <input id="last-name" type="text" required /></label>
<label for="email">Enter Your Email: <input id="email" type="email" required /></label>
<label for="new-password">Create a New Password: <input id="new-password" type="password" pattern="[a-z0-5]{8,}" required /></label>
</fieldset>
<fieldset>
<legend>Account type (required)</legend>
<label for="personal-account"><input id="personal-account" type="radio" name="account-type" checked /> Personal</label>
<label for="business-account"><input id="business-account" type="radio" name="account-type" /> Business</label>
</fieldset>
<fieldset>
<label for="profile-picture">Upload a profile picture: <input id="profile-picture" type="file"/></label>
<label for="age">Input your age (years): <input id="age" type="number" min="13" max="120" /></label>
<label for="referrer">How did you hear about us?
<select id="referrer">
<option value="">(select one)</option>
<option value="1">freeCodeCamp News</option>
<option value="2">freeCodeCamp YouTube Channel</option>
<option value="3">freeCodeCamp Forum</option>
<option value="4">Other</option>
</select>
</label>
<label for="bio">Provide a bio:
<textarea id ="bio" rows="3" cols="30" placeholder="I like coding on the beach..."></textarea>
</label>
</fieldset>
<label for="terms-and-conditions">
<input id="terms-and-conditions" type="checkbox" required /> I accept the <a href="https://www.freecodecamp.org/news/terms-of-service/">terms and conditions</a>
</label>
<!-- User Editable Region -->
<input type="submit" value="Submit" />
</form>
</body>
</html>
I suggest you spend some time reading the instructions and the hint carefully and try to understand what they tell you, often understandting the text is enough to know what to do