In c++, I can create instance with `Klass k`, can I never use `new Klass() `?

Java and c# has not "new Klass() return instance ptr" feature and I can use java and c# do most things, I don't understand, why c++ has new Klass() return instance ptr, why I need use it, can I never use new Klass() and use Klass k instead of?