How do I get a previous Physically bought game back on my new-gen Xbox series S

You would have to own it digitally in order to play it on the Series S. However, that game has been discontinued so the only way to play Minecraft: Xbox One Edition is by disc.

I've been seeing a lot of negativity online over the new xbox one s. To be completely honest most of my games are digital purchases. I normally only by physical copies of older games to add to my collection of previous gen titles (which I never go back
and play anyway). So on that basis I would be more than happy to go out and purchase a digital only console. I do need a new system at the moment anyway so I'll hold out for release and go get one.

Thank you for the reply.

The FAQ states the following:

• If you’re playing from disc on Xbox Series X|S, you’ll need to keep the disc inserted to play that game.
  

This implies if I bought a disc and installed on my xbox one, I would require the disc to play on my Series S. However the Series s is discless. I don't understand how a physical disc can state smart delivery for the Series S.

I just bought a brand new Xbox One X, but when I go to the store, Flight Simulator and other Xbox Series X/S games say they are "not playable on this device" and I can't get Flight Simulator to install on my brand new Xbox One X because it says it's "not compatible". Very frustrating.

So you bought an Xbox One X and expected to be able to play an Xbox Series X game on it?

Why would a game made for an Xbox Series X work on an Xbox One X?

If you want to play Xbox Series X/S games I would take your brand new Xbox One X back to the store you bought it and see if they will take it back and you could try and buy an Xbox Series S (Series X consoles are very hard to find, but a Series S can be found fairly easilly)

I do want to get the new Xbox Series S, so if i get the standard edition i will have it there (Xbox Series S) to right?

You'll be playing the Xbox One version on the Series S. There may be some enhancements made to the next-gen version that you won't have unless you buy the other version.