[horde] Where is the current documentation ? Howto install on Debian 9 ?

[Kallen Petr]

Hallo.
Please, where can I found current documentation ?

I would like to test “Horde Groupware Webmail”.
I am looking for “step-by-step” or admin documentation howto install it on Debian 9.

Command "apt install php-horde-groupware" works well, but, what now ?

Where to start to configure and setup DB ?
What will be the first steps ?

LAMP is UP and running.
Mailserver (postfix, dovecot, rspamd, dkim) too.

Thanks for a help.
This is my first time when I see Horde project and it looks verry fine and sexy, but documentation is not sufficient.

But OK,
If there's someone who installs it for me, I'd like to pay :-)

Best regards,
Petr Kallen