Get post content by usingpost id in wordpres

function custom_content($post){
 
 
$my_postid = 6;//This is page id or post id
$content_post = get_post($my_postid);
$content = $content_post->post_content;
$content = apply_filters('the_content', $content);
$content = str_replace(']]>', ']]>', $content);
echo $content;
 
}