sore

Question
my dog has a sore on the side of his genitals with puss in it he also has green ooze on the tip of his penis what is this

Answer
Please forgive the lateness of this answer but my Internet connection has been down completely for two days.

This could be anything from a self-induced lick wound to a sticker in his sheath wound and infection.
This is something a vet would have to see to help you with. I cannot see it and cannot diagnose it.
Call the vet and get him in for an appointment before it gets worse.