How to hide sensitve page from google spiders and non-membres in wordpress!

Use password protection mechanism

Alterative you can use wordpress hook in your theme to show your post/page only for administrators this way:

add_action('wp', function() {
  if(is_page('my-data') && !current_user_can('manage_options')) 
    die("123")
});

Note: don’t use this code. It is just for demonstration. Better use hook template_redirect or something else.

We need more info about your environment to answer more specifically.

Perhaps the best option for you would be set password by http-server.
For apache using .htacces with something:

AuthType Basic
AuthName "restricted area"
AuthUserFile .htpasswd
require valid-user