This is making me frustrated.

So we have this Cane Corso named Ace, he is 120lbs and such a goob. He was supposed to be the family dog but he has unfortunately taking a liking to someone in the house who refuses to take him outside and even lies about it, he kicks the dog out of his room when he is doing ANIMAL THINGS. The only reason why the dog likes him is because he will just hand him people food. My boyfriend walks into his room and watched him just give the dog an entire pizza crust. What can I do to get the dog to like me more, I am trying so hard to train this guy but the other person thinks he is entitled to him because he likes him more and doesn’t do anything I ask to help train the dog. In fact he does the complete opposite. Im just worried that something will click in this dogs head because he isnt getting any corrects with anything wrong he does, he just gets told to “go lay down”.