How To Add Filter/Search Table in Blogger and Wordpress with guidance

Demo:

 Code :

<style>
* {
  box-sizing: border-box;
}

#myInput {
  background-image: url('https://img.icons8.com/ios/20/000000/search--v1.png');
  background-position: 10px 10px;
  background-repeat: no-repeat;
  width: 100%;
  font-size: 16px;
  padding: 12px 20px 12px 40px;
  border: 1px solid #ddd;
  margin-bottom: 12px;
}

#myTable {
  border-collapse: collapse;
  width: 100%;
  border: 1px solid #ddd;
  font-size: 18px;
}

#myTable th, #myTable td {
  text-align: left;
  padding: 12px;
  border: 1px solid #ddd;

}

#myTable tr {
  border-bottom: 1px solid #ddd;
}

#myTable tr.header, #myTable tr:hover {
  background-color: #f1f1f1;
}
</style>
<input type="text" id="myInput" onkeyup="myFunction()" placeholder="Search for names.." title="Type in a name">

<table id="myTable">
  <tr class="header">
    <th style="width:60%;">Name</th>
    <th style="width:40%;">Country</th>
  </tr>
  <tr>
    <td>Alfreds Futterkiste</td>
    <td>Germany</td>
  </tr>
  <tr>
    <td>Berglunds snabbkop</td>
    <td>Sweden</td>
  </tr>
  <tr>
    <td>Island Trading</td>
    <td>UK</td>
  </tr>
  <tr>
    <td>Koniglich Essen</td>
    <td>Germany</td>
  </tr>
  <tr>
    <td>Laughing Bacchus Winecellars</td>
    <td>Canada</td>
  </tr>
  <tr>
    <td>Magazzini Alimentari Riuniti</td>
    <td>Italy</td>
  </tr>
  <tr>
    <td>North/South</td>
    <td>UK</td>
  </tr>
  <tr>
    <td>Paris specialites</td>
    <td>France</td>
  </tr>
</table>

<script>
function myFunction() {
  var input, filter, table, tr, td, i, txtValue;
  input = document.getElementById("myInput");
  filter = input.value.toUpperCase();
  table = document.getElementById("myTable");
  tr = table.getElementsByTagName("tr");
  for (i = 0; i < tr.length; i++) {
    td = tr[i].getElementsByTagName("td")[0];
    if (td) {
      txtValue = td.textContent || td.innerText;
      if (txtValue.toUpperCase().indexOf(filter) > -1) {
        tr[i].style.display = "";
      } else {
        tr[i].style.display = "none";
      }
    }       
  }
}
</script>

For customization :

To customize the search box :

#myInput {
  background-image: url('https://img.icons8.com/ios/20/000000/search--v1.png');/* Change the image */
  background-position: 10px 10px; 
  background-repeat: no-repeat;
  width: 100%;
  font-size: 16px;/* Change the font size ,if you want to change font colour just add "color: black;" */
  padding: 12px 20px 12px 40px;
  border: 1px solid #ddd;/* Change the colour and size of border */
  margin-bottom: 12px;
}

To customize the table :

  
#myTable {
  border-collapse: collapse;
  width: 100%;
  border: 1px solid #ddd;/* Change the size and colour of border of the table */
  font-size: 18px;/* Change the font size ,if you want to change font colour just add "color: black;" */
}

#myTable th, #myTable td {
  text-align: left;
  padding: 12px;
  border: 1px solid #ddd;/* Change the colour and size of border of cells and rows */

}

#myTable tr {
  border-bottom: 1px solid #ddd;
}

#myTable tr.header, #myTable tr:hover {
  background-color: #f1f1f1;/* Change the colour of header and hover */