Lots of 360 games are backwards compatible and available digitally via the store. There's currently an early UWP build of Xenia, you'll find guides on how to install it on your Series S via dev mode, but it's still more like a proof of concept and won't make for a smooth experience yet.

Dose skylanders work

Buddy, I'm not going to download and test a specific game running on Xenia UWP for you. Try it yourself and see.

the thing is when I went to the store the first time, The only One that was actually available for purchase was skylinder's super chargers

If the other ones were either not there or unavailable

I've already explained that any 360 game not available in the store can, in theory, be emulated via Xenia. Not sure what else you expect me to do for you here. If you're desperate to play a game that isn't available to purchase, go check out a guide on how to install Xenia on your Series S and you might get lucky. Some games are running fine.

From disc to digital? No.

On Series X, there are about 600 Xbox 360 games that are backward compatible via the original disc. The Xbox website has a list to see if your game is included.