i want a script for when i shot 3 trigers a song coming up i hope you can help me 

i want a script for when i shot 3 trigers a song coming up i hope you can help me 

Check out my latest tut on script to radiant. It goes over making a shootable ee, and you could make a song the reward. There are slot many many shootable scripts in the dl section.

Edit:
If your question is how to make a song the reward, then that is something else. You would add it to a soundalias such as user_alias.csv, I would make it a 2d sound, or make a new one and add that to your mapname szc file. Then playsoundatposition("soundname",(0,0,0)); should work for the reward.