I am streaming , how can I play music when provider goes down.

I only use Flac files no fm tuner, or phones I want to be able to access my Flac files 

how to access them ,and how to play files and pick music to play ,

when my service provider is down ?

iwas even thinking in the future like my friend to spend $500 for the Tesla starling setup then pay the $100+ for music and Audio , at a later date .

Roon 2.0 requires an active Internet connection at all times to work. And obviously Qobuz does as well. If your Internet connection goes down, use different software to access and play the locally stored music.

When the network (often) goes down you lose all remote control of a network player (streamer.)  You could load a "party" (huge) playlist (if you have the files) on random. It will continue to play but remote control will be lost until the network comes back up. I know of zero non network players available in 2023. I'm keeping mine.

I use a Aurender with a 2TB SSD and have like 500 CS on it, I can listen to that if my Internet goes out. Or get starlink