How Do I upload music from my ipod to my itunes(computer)?

I'm asking because i get my music from my cousin and I want to keep the music on my computer as well, however his computer broke so i needa upload his music onto my computer till he gets a new one. Also I have been searching on the internet but all the sources I found were outdated. So anyone know how i can transfer my ipod music to my itunes/computer without downloading anything? And if not any free downloads I could use? Thanks!!!