Hi @georgekosmidis, you found the right place to ask
If you use Kibana, you will always need to install both Elasticsearch and Kibana plugin (choose between Free, PRO or Enterprise).
The LDAP connector is part of the Elasticsearch plugin, so the Kibana Free plugin can suffice. But keep in mind the functionality will be very limited, and you won’t be able to hide apps, add CSS/JS, use multi tenancy, etc.
A good place to start is our all in one demo docker container: it has a demo of ROR Enterprise, and you can explore the docker file as a recipe for the configuration of the various parts.
Don’t forget to hit the official docs for some examples, and manuals