How to add "READ MORE" tag in wordpress Post..??

This the method to To add you "READ MORE" option in word press post or page..

NOTE: (243 is the dummy id)

$post_id2 = 243;
$queried_post2 = get_post($post_id2);
$title2 = $queried_post2->post_title;
echo substr($queried_post2->post_content,0,243);

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