Hello,
Some child themes like from Genesis from (StudioPress) have their own inbuilt SEO fields for each page.
Please be more clear, provide us parent theme name as well as child themes used.
Make folders like for blog make it yourdomain.dom/blog and use blog page template for this folder..
No need to install multiple subdomains, Google like small single domain sites better organised with navigation and clean layout
site: shows few 404 pages, are you using 301 redirection from another domain to this one, if so, paste you .htaccess file and issue is in 301 redirect….
