HI
Can you share more information like screenshots, logs- Its most important information. Also it would be good if you could share your kibana.yml and elasticsearch.yml configuration - of course commenting out the sensitive information.
My guess is that Kibana cannot connect to the ES cluster.
Are you running X-Pack with security enabled? If so, did you set a password for the kibana user, and add it to kibana.yml ?
See: https://www.elastic.co/guide/en/x-pack/6.0/setting-up-authentication.html#set-built-in-user-passwords