How can I discpline my brother?

He is 5 years old im his brother guardian who is taking care of him. When he was doing the egg hunt at our house he got really angry that he want to do it again. But I told him no you did it already then he got really upset and stomping his feet. Yelling I want to do it again every time I told him no he got very frustrated. That he was kicking his eggs away and dropped his basket saying to me leave me alone I dont want to talk to you. I tried to calm him down but he kept getting very angry

What should I do