how to convert dvd's and blu rays to digital store them and play them back on your TV?

Just use a ripper program. There are gobs of ’em.
Put them on a drive and plug them into a player.
Roku Ultra $80. Old ones work fine too. Or a Samsung, LG or TCL TV.
Are you late to the party or what?
Been doing this for 20 years. Just to avoid previews and other BS when all I wanna do is watch a movie.
Now.
I travel with an old Roku and mucho movies on a SSD. 

How do I get my movies on the  Zappitti media player?

Your movies ( music ) are stored on the Zappitti NAS.
The NAS is connected to your network ( Ethernet )
The Zappitti media player in connecte to your network ( Ethernet )
The media player detects the NAS and all the movies ( music) in it.
Probably , Apple TV 4K would detect the NAS too.

Zappitti media player ( I think )
https://www.amazon.com/Zappiti-One-SE-4K-HDR/dp/B07DLWVYQX

You need a ripper program. Once the discs are converted to files you can play them with Plex media server (free) on a smart TV or Roku, Chromecast, Fire Stick etc connected to the same network. I can play anything on the computer via Plex. It’s just faster with better control plugged in. I use one ripper for mono and another for surround. But to decode dts they have to be played via my Sony BluRay.
I don't have a clue what the Zapiti (?) is good for.
Except lightening your wallet. You can buy a ripper program and a used Sony to play it on. for <$100.

$30

https://www.techclassy.com/wonderfox-dvd-ripper-pro-review/

Or if you know how, find a free one.
I’ve got a free Blu one but never got around to getting a cheap Blu drive for the PC.