Downwnload hi res music to NAS external drive

Can anybody tell me how to download hi res music tracks to my WD Cloud external NAS Hard Drive.

The music I have on it at the moments has all been from cd rip software and uncompressing files.

I want to do the download in in hi res and without having to buy cds ecptc.

I hope somebody can help as I am not that good at this type of tech.