Hi Kerry,
How to set need to admin approve to post ?
In the ACL section of EasyBlog backend, you have to configure those user group's 'Allowed To Publish Post' permission(
http://take.ms/Kj5zU) if you want the new posts from the users under that user group to be moderated first before they are published.
Why the login page no register new user?
For Joomla's login page, you would have to enable '
Allow User Registration' setting in your backend(
http://take.ms/BW0OO). Click on the options button at the top right of Joomla users page to access the user options page.