Connect Arduino to music and my motion dector light device

Hi there, can someone please tell if if I could connect a Arduino device (and which one i should by for that!) to my motion detector led lights (light go on when activated by movement) AND TO a mp3 (with the music I set up on it)....

The motion detector is powered to 1.5 V batteries (or other batteries available as well) and i need it to trigger the music when the light is also triggered by the motion detector..

Any advice?? Is it hard to do it?! and what Arduino should I buy for that?

Please bear in mind that I'm not tech minded, nor a geek or anything. i came accorss Arduino by a simple advice (connect Arduino to an MP3).. Thank you so much :)

You need to provide a link to the devices you have before we can tell you what you need to do.

You need to provide a link to the devices you have before we can try to tell you what you need to do.