Q: When i receive iTunes music as a gift, where do i find the code to redeem it?

Hello Foinoire,

Thank you for using Apple Support Communities. 

So, you received an iTunes Gift Card and are looking to redeem it? The following articles should provide you with what you need to know to redeem the code and get your music:

Redeem and use iTunes Gift Cards and content codes - Apple Support

or

iTunes 12 for Mac: Redeem an iTunes allowance, gift certificate, or Gift Card

iTunes 12 for Windows: Redeem an iTunes allowance, gift certificate, or Gift Card

Regards