if you had the ability to cause major change in the world , what would you change and why

If I had the ability to cause major change to the world,  I would like to make the world peace.  Some places still having war,  in my opinion , I think that war is the worst thing in the world . I want  peace because war makes people feel pain, sad and more. Because of war,  people lost their family, in just a few days or maybe second ,  they suddenly become orphan , and they are lost. War also cause them health problem,  having war will make the environment worse,  it may cause them breath harder than usual . Babies haven't been born will become deformity . This is the reason why I want to make war stop.