Hey @stoopxhangs,
Welcome in the Spotify community! 🙂 I'm sorry to tell you that it isn't possible to save your spotify music on your Ipod classic. To use spotify music you need a Spotify application and there is no app-store for the Ipod classic (Only Ipad, Iphone, Ipod touch).
There is a similiar question where you can find more information about this: Synching offline music to iPod Classic
I hope I was able to help you 🙂
Specialworld
I don't know what Spotify is doing. No more support Symbian and you aslo Cant sync annymore. Why could we sync back in time than ?