//My Form
<form id="someform">
<div class="input-group">
<textarea placeholder="Post your Comment Here ..." name="post" class="form-control custom-control" rows="3" style="resize:none"></textarea>
<span class="input-group-addon">
<button type="submit" name="post_comment" class="btn btn-primary">
Post
</button>
</span>
</div>
</form>
//your text area get value to URL
<?php
if(isset($_POST['post_comment']))
{
echo htmlspecialchars($_POST['post']);
}
?>
//print the value using get
echo $_GET['post'];
//url must be like this
http://localhost/blog/home.php?post=asdasdsad&post_comment=
//post value has asdasdsad so it will print to your page