Idk if lucky patcher still exists, but i used it for a while.
If its an online game there’s not much to do.
If its an offline game that shows ads when you’re connected to the internet, then you can install a private local vpn like Tracker Control to specifically disable internet access to that app.
Invizible Pro also works iirc, but that might be overkill for your purposes.
Private DNS like NextDNS others didn’t work correctly for me but YMMV