Moved wp is so broken. Que es la overall theory of dirs, permalinks, rewrite rul

When I changed servers I decided to put my old wp in its own directory. I followed https://codex.www.ads-software.com/Giving_WordPress_Its_Own_Directory, read about https://codex.www.ads-software.com/Using_Permalinks as well as https://codex.www.ads-software.com/Creating_a_Static_Front_Page. Some how I have gotten things in a terrible convoluted state. I am in an infinite loop of change in .htaccess, index.php, permalinks and static pages with something always left broken. I need to know the concept instead of following ‘copy don’t move this’ , ‘update your permalinks that’.

It might be a problem that I named the subdirectory ‘blog’.

The state right now is: I can get to wp-admin (whew). The site loads but not with the static page but with the blogposts. It shows the blogposts but if I click on a particular blog post it 404’s. Tags and categories 404 too. The state of the settings is:
in root:
index.php is

<?php
define('WP_USE_THEMES', true);
require('.blog/wp-blog-header.php');
?>

.htaccess is

<IfModule mod_rewrite.c>
# BEGIN WordPress
RewriteEngine On
RewriteCond %{HTTP_HOST} ^(www.)?sitebuilt.net$
RewriteRule ^(/)?$ blog [L]
# END WordPress
</IfModule>

in /blog:
index.php is:

<?php
define('WP_USE_THEMES', true);
require('./wp-blog-header.php');
?>

.htaccess is

<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d

settings->permalinks is /%postname%/

pages->static_homepage is called ‘home’, the permalink is https://www/sitebuilt.net and it won’t let me change it.

pages->place-holder_for_posts is called ‘blogposts’ and its permalink is https://www/sitebuilt.net/blogposts

With this setup permalinks are right off the hostname and it can’t find them. I’ve changes stuff so permalinks say https://www.sitebuilt.net/blog/mypost and it still can’t find them. Where are they? What’s the theory of operation?