Cancelling a Gamepass subscription on a account i’m game sharing with

so i recently started game-sharing with this friend of mine. However he has a subscription already which is xbox live core, and i wanted to game share game pass ultimate with him so if i cancel his subscription will he have access to my ultimate if i do cancel his subscription and if not how so? the reason i want to game share game pass ultimate with him is for these certain games i play that he doesn’t have access to due to him having xbox live core and not game pass ultimate so in this situation what do i do please respond back as soon as possible

:)