Digital streaming/library


I have purchased a rather substantial 2 channel audio system, and two of the components are a streamer and an audio nas...a melco. I want to build a digital music library. I would love to have the hd level tracks, but the downloads are so expensive. I already have thousands of lps, and thousands of cds. I have iTunes, and it (and rhapsody) allow you to download tracks into your computer...but they are not cd quality. I have a streamer, and I could get the tidal or deezer hi res subscriptions, but do they allow you to download tracks into your computer/nas drive for a digital library?
128x128easola01
easola01, I'm not familiar with streaming.  My whole library consist only of CDs on HD  in ALAC format.
Thank you for your input kijanki. I must confess, your informed advice is above my head, but I want to do things right. Since it seems I am unable to build a lossless library from tidal or deezer, maybe I will do what cds I have your way. 

So what do I do...are you saying I need to get this audio media, and that alone will convert cds to library from itunes to my storage as 16/44.1? Sorry, I need baby steps here
I rip data out of my CDs using (free) XLD for MAC.  I store ripped data in ALAC format, that is lossless compressed file.
Perhaps the best program you can use with Windows is free EAC (Exact Audio Copy).  This program will try to go over same unreadable sector more times than ITunes, that eventually will start interpolating or even dropping out samples - big advantage with scratched CDs, not so much with new.  Selecting format to use is another story.  ALAC, that I use, is more of an Apple thing, while FLAC is not supported by Itunes.  Best choice for you might be AIFF because it can hold metadata.  It takes more space than FLAC, but storage is cheap, these days.  Be sure to create backups.