Please explain

I tried using the parents constructer without the super keyword in child class but it didn’t worked out so what is the meaning of the 3rd point

By default, child classes will inherit its parent’s constructors. If you want to modify those inherited constructors, you can use super(). Or, if you want to completely change the constructors, you can “override” them (it’s not technically method overriding because constructors are not methods) by declaring a new constructor in the child class.