Can I play different games on xbox series x and xbox one at the same time

So I just got a new series x and I'm giving my old xbox one to my son. (He has a number of games he plays under my gamertag) every time I try to play a series x game it stops him from l playing the xbox one(a different game) Is there a way to play different games at the same time on both consoles at the same time?

:)