Well kiddo, "Make love, not war" is a phrase that means people should focus on loving each other instead of fighting and going to war.
When people make love, they are showing affection and care for each other. They are hugging, kissing, and doing other loving actions.
But when people go to war, they hurt each other, damage things, and even kill each other. This is not a good way to solve problems.
So when people say "make love, not war," they mean we should try to solve our problems by being kind and loving towards each other. By doing this, we can create a world without wars, full of peace and happiness.