Android | online database

Hy all,
I would like to create a game for Android, and I would like to be able to connect to an online database, I have documented but I still have a lot of confusion,
If I create a database in MySQL I can put it online? (Registering the domain)

once put online, I can do that from the game I can read the data stored in it?

Sorry for the bad english,
Thanks in advance

This is not really a Unity question. Typically you have a web server, which has some PHP or similar that talks to the database. You can then make GET and POST requests to the PHP to read and write data. On the Unity side you just need to use the WWW and WWWPost classes.

Read something about RESTful services. You have server (written in Java, .NET, PHP, etc) hosted on the internet. You create POST, GET HTTP requests to your server. Server handles your request and sends response (JSON, XML or simple String). Inside Unity you should read something about WWW, WWWForm.