How to Replace the Default WordPress Admin Dashboard

In order to replace the default WordPress dashboard, you have to redirect to another admin URL in case a user tries to access it.

In the example below we redirect the users to the posts table and the URL is edit.php. Change it with the one that you want.

Add the function below in order to redirect the user after login: 

 //redirect users after login to wp-admin
function ik_redirect_dashboard_after_login( $redirect_to, $request, $user ){
   $redirect_to = admin_url( 'edit.php' );
   return $redirect_to;
}
add_filter( 'login_redirect', 'ik_redirect_dashboard_after_login', 9999, 3 );
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Add the function below in order to redirect all the requests from wp-admin/index.php to wp-admin/edit.php :

 // redirect all the dashboard requests
function ik_redirect_dashboard(){
   wp_redirect( admin_url( 'edit.php' ) );
}
add_action( 'load-index.php', 'ik_redirect_dashboard' );
PHP