Will my Series S console play a digital Series X game?

You have names mixed up. There are no consoles named the Xbox One Series S or Xbox One Series X.

The Xbox One/One S/One X all have a disc drive.

The Xbox One S All Digital Edition does not have a disc drive.

The Xbox Series X has a disc drive.

The Xbox Series S does not have a disc drive.

All the consoles can play backward compatible games. The Series S and One S all digital edition can only play games digitally downloaded.

The other consoles can play games from disc and from digitally downloaded,

I hope this clears things up for you.

There is no One is series consoles

Xbox one games are not listed by x or s

They are all xbox one games

Series consoles are xbox series s or x that's it

Digital or disk thata all the options you get

Series x consoles are NOT xbox ones

They ate just xbox series x or s

It's to avoid confusion xbox one games are compatible with xbox one all versions except for disk games on digital and can use hdds

Vs series consoles all digital series content work on series consoles

But disk games work only on disk consoles and next gen storage

I’m confused how will it work for both if one is physical and the other is digital

Both consoles are digital...it's just the Series S is Digital only whereas the Series X is both Digital and Physical.

75th Anniversary Edition Pre-Order can be downloaded to the Series S, the Series X and the Xbox One

Hi,

Regardless of that consoles you own, the Series S is digital only. It will only play downloaded digital licensed games. It will not check if you have the disc in another one of your consoles. If you intend to purchase many of your games still on disc an
additonal console in the Series S may not be for you.

If have lots of games on disc, then another Series X would be the better option.