Xibo and Homepage like www.xxxxx.de/xibo

We have a website and an agency processed these Page. Now let there install it as still as Xibo can access it:
xxxxxxx.de/xibo
Unfortunately we have problems creating the SQL database. I get the database name from my agency and password. In addition, I have received the localhost. Where it is but fails the admin username and admin password !!! Where can I get that? know that my agency?
About tips I thank you

If there’s an empty database already for you to install in to, you should use the existing database route in the installer. If it’s asking for admin credentials then you’re using the route that also tries to create the database.

Ok thanks alexstrong text