Hello,
1/ It looks like breadcrumbs are disabled, because we have the next settings – https://prnt.sc/lDp5pHcWWPql
If you do not want to enable the breadcrumbs for pages, you can add h1 manually on pages, or do this via additional customization the child theme files.
Please note that additional customization is outside the scope of our basic support.
2/ https://www.wpbeginner.com/plugins/how-to-minify-css-javascript-files-in-wordpress/ https://xstore.helpscoutdocs.com/article/100-how-to-speed-up-my-website
3/ https://kinsta.com/blog/make-fewer-http-requests/
4/ https://www.wpbeginner.com/wp-themes/how-to-add-facebook-open-graph-meta-data-in-wordpress-themes/
Also, check available settings in Theme Options > SEO.
Kind Regards,
8theme team