How to instance classes?

[Androz2091]

Hello, I want to now if it's possible to create a new instance of a class from a js file. And if it's possible to add it if it's actually impossible.
Here is my code:

HAI
    CAN HAS MYPACKAGE "myPackage.js"
    I HAS A CLIENT ITZ MYPACKAGE 'Z Client
    VISIBLE CLIENT BTW  class Client extends AnotherClass {...
    CLIENT WIZ ENUF BTW TypeError: Class constructor Client cannot be invoked without 'new'
KTHXBYE

Please I really need this feature 🙏