Hello!
You have installed Community Server only i suppose. Also there must be installed Documment Server to edit files.
I advice you to install
Community Edition (free version with limited connections and cpu cores) or
Enterprise Edition (full version with 30 day trial key). Trial 30 day activation key for Enterprise Edition you can download
here, but you must fill in the form.
Or you can install the Document Server separately and connect servers, but i think it's hard way.