Hi, welcome to justanswer.com! My name is Mike.I am going over your question and I will be with you shortly.
You don't purchase music you just play it. You are buying music the normal way and not turning on the Apple Music subscription. In iTunes go to Browse you should see the offer for Apple Music.
You can try it free for three months then use your gift card: http://www.apple.com/music/
If you are satisfied, please kindly provide an OK or Above Rating - so I get paid. Keep in mind you can always come back to this page at any time regarding this question. Thanks!!
As long as you are purchasing the Apple Music subscription I'm sure Apple will refund the purchases. http://www.imore.com/how-to-get-refund-itunes-app-store
It allows you to play any music in the Apple Library so you don't need those purchases.
Do you understand?
Please let me know if you need further help with that or if we are finished... thanks.