In i Tunes you creare a library by either ripping your CD's to it or buying via the i Tunes store.(I only ues i tunes vouchers for this and when you redeem them the store "knows" how much credit you have left.) When you sttach the i Pod, Synching is where you allow the i Pod to acquire the whole or some of the library, As I have a number of i Pod users on my PC (Self, grand children) and we all have different tastes, I prefer to set preferences NOT to automatically synch. First, with a voucher, in iTunes, ensure you have created an account - usually your e Mail and a password, with address etc. Follow the prompts. Then in "Store" you should be able to browse by title, artist or genre.Later you can create playlists. Do ask specific things as this is a big subject!
iPhone 7 review: a range of small updates add up to an excellent phone