Check out example codes for "w3schools contact form". It will help you in understanding the concepts better.

Code Example 1

/* Style inputs with type="text", select elements and textareas */
input[type=text], select, textarea {
  width: 100%; /* 
  Full width */
  padding: 12px; /* Some padding */  
  border: 1px solid #ccc; 
  /* Gray border */
  border-radius: 4px; /* Rounded borders */
  box-sizing: border-box; 
  /* Make sure that padding and width stays in place */
  margin-top: 6px; /* Add a top margin */
  margin-bottom: 16px; 
  /* Bottom margin */
  resize: vertical /* Allow the user 
  to vertically resize the textarea (not horizontally) */

/* Style the submit button with a specific background color etc */
input[type=submit] {
  background-color: #4CAF50;
  color: white;
  padding: 12px 20px;
  border: none;

    border-radius: 4px;
  cursor: pointer;

/* When moving the mouse over the submit button, 
  add a darker green color */
input[type=submit]:hover {
  background-color: #45a049;

/* Add a background color and some 
  padding around the form */
.container {
  border-radius: 5px;
  background-color: #f2f2f2;
  padding: 20px;

Code Example 2

<div class="container">
  <form action="action_page.php">

  <label for="fname">First Name</label>
    <input type="text" 
  id="fname" name="firstname" placeholder="Your name..">

  <label for="lname">Last Name</label>
    <input type="text" 
  id="lname" name="lastname" placeholder="Your last name..">

  <label for="country">Country</label>
  id="country" name="country">
      <option value="australia">Australia</option>
  <option value="canada">Canada</option>
  <option value="usa">USA</option>

  <label for="subject">Subject</label>
  id="subject" name="subject" placeholder="Write something.." 

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