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The problem is with how to edit posts.One solution would be to install this plugin.
The process of installing the new WordPress or making changes does not allow you to add new plugins to the Plugins menu.
Download the Classic Editor plugin to unzip and then copy it to the plugins folder.
[root@desk mythcat]# cp -r -f /home/mythcat/classic-editor/ /usr/share/wordpress/wp-content/plugins/
Activate this plugin and now you can create and edit pages and posts in WordPress.