VW Polo 9n 2007: How to Program Alarm Remote, Key Details & Attachment Picture Explained

Hello, I have a VW Polo 9n 2007. And I have an alarm remote for it and I don't know how to program it
In the attachment I send a picture of the key and one more thing for us what this little key is for.
greetings

A small siren key, in the remote control you can only change the batteries, with the rest for alarm service.

And this key what it does

If you unplug the battery, it will be useful to turn off the mermaid