how to set up a database

This is my first time using a database in unity. Here are some questions;

  1. What database is good to use in unity
  2. Some tutorials on how to do it.
    thanks

As far as I know, Unity does not support database. You can use external code such as XML or SQL; some kind of .NET code to save the information and import it when you please.

This depends on what you want to make. You could for instance use an SQLite database or (as mentioned above) use XML.