Potty training 2 year old boy.

Hey ladies. I am having a war with my son who will be two in December. His older brother was 1.5 when I started him on potty training he went the first time I set him on the potty. My younger one will have nothing to do with the potty. Hes used it twice out of 30 times. Every time I try to get him to sit on it and go he wont use it and than will scream and cry until hes aloud off. It doesnt matter if I make him sit there for 30 min or 2min or multiple times a day for 5min each. He will not use it and just screams and cries every time hes on it. (Just a small training potty). Than when he is aloud up he will immediately go after the diaper gets put back on or I've let him run free a couple times and hell go on the floor. Weve tried taking a couple months breaks between and hes still doing the same thing. He points at his diaper and says peepee after he pees. He will sit on the little potty if I'm going if hes dressed. He shows signs of being ready but refuses to go. Any advice???