how do I make melee attack in a top down in wick editor
Easy! You just make a hit-box and a hurt-box.

Yellow: Hitbox (what hits other mobs)
Red: Hurtbox (what other mobs hit to hurt you)
for(mob of exampleLayerWithBadMobs) {
if(this.hitbox.hits(mob.hurtbox)) mob.Health -= 1.5;
}