Is there any plugin which can paste a common content to my every post?

Actually you don’t need a plugin to do this. Just add a simple function to your functions.php file:

function my_content($content) {
  $content="My content before post" . $content . 'My content after post';
  return $content;
}
add_filter('the_content','my_content');

If you don’t want additional content to appear in your feed, use following function:

if( !is_feed() ) {
  function my_content($content) {
    $content="My content before post" . $content . 'My content after post';
    return $content;
  }
  add_filter('the_content','my_content');
}