Someone said God created evil, how do i respond to them?

My friends keep telling me that since God created everything, it means he also created evil. How do i respond to them? Is this true?

No, it is not true. God did not create evil, no one “created” evil per se. Evil isn’t a thing, but an absence of a perfection that is due to a creature. Evil is understood as a void. It is like darkness which is simply an absence of light and not a ‘thing’ in itself.