ref https://geekflare.com/show-featured-image-in-wordpress-single-post/

รวมทั้งรูปในโพสท์

<?php

$id = 4; // The Page or post ID
$page_data = get_post( $id );
$title = $page_data->post_title;
$content = $page_data->post_content;
$excerpt = substr($content, 0, 155);
$featured_image = wp_get_attachment_url( get_post_thumbnail_id($id, 'thumbnail') );

?>

<div class="post">
<h1><?php echo $title; ?></h1>
<div class="featured"><img src="<?php echo $featured_image; ?>" /></div>
<p class="excerpt"><strong><?php echo $excerpt; ?></strong></p>
<p class="content"><?php echo $content; ?></p>
</div>

ref. https://wordpress.stackexchange.com/questions/162162/how-to-remove-images-from-showing-in-a-post-with-the-content
https://wordpress.stackexchange.com/questions/76453/get-post-excerpt-and-title-by-specific-post-id
Excerpt
https://wordpress.stackexchange.com/questions/177836/how-to-display-a-single-post-excerpt

https://stackoverflow.com/questions/8696206/wordpress-excluding-images-inserted-into-post-from-get-children

Remove All Images from the_content in a Post

<?php echo preg_replace('/<img[^>]+./','',get_the_content());?>

https://wordpress.stackexchange.com/questions/193511/formatting-post-content-to-exclude-gallery
https://wordpress.stackexchange.com/questions/87909/how-to-retrieve-text-only-from-wp-content-not-from-wp-excerpt
https://wordpress.stackexchange.com/questions/220293/how-to-remove-only-images-from-the-content
https://wordpress.stackexchange.com/questions/162162/how-to-remove-images-from-showing-in-a-post-with-the-content
https://www.google.com/search?q=get+content+exclude+image+wordpress&oq=get+content+exclude+image+wordpress&aqs=chrome..69i57j69i64.23457j0j4&sourceid=chrome&ie=UTF-8
https://wordpress.stackexchange.com/questions/77159/function-to-show-only-featured-image-of-the-posts
https://wordpress.stackexchange.com/questions/147844/how-do-i-grab-specific-posts-by-post-id-and-display-the-title-featured-image
https://wordpress.stackexchange.com/questions/12498/get-the-excerpt-by-id
https://www.google.com/search?q=how+to+show+featured+image+specific+post&biw=1366&bih=661&sxsrf=ALeKk029jRVFN99RMohSASUqwsd1qD7P9Q%3A1624687920759&ei=MMXWYPXvLYPfrQHYvZK4Dw&oq=how+to+show+featured+image+specific+post&gs_lcp=Cgdnd3Mtd2l6EAM6BwgAEEcQsANKBAhBGABQjg5Yjg5gtxtoAXACeACAAfMCiAH5A5IBBzAuMS4wLjGYAQCgAQGqAQdnd3Mtd2l6yAEIwAEB&sclient=gws-wiz&ved=0ahUKEwj1x4yT0rTxAhWDbysKHdieBPcQ4dUDCA4&uact=5