How to call a function from class where instance of another class

I’d like to ask you if there is another way to call function from a class where this INSTANCE of another class is coming from?

Or do you think my approach is correct?

class App(){
  constructor(){
    this.interface = new Interface();
  }

  refresh(){
  ...refresh app somehow...   
  }
}

class Interface(){
  constructor(){}

  changeInterface(){
    ...change interface somehow...
    this.App.Refresh(); // => I need to call this function from previous class
  }
}

var myGlobalVariable = new App();
    myGlobalVariable.interface.changeInterface();

Only I can think of is to use global variable inside…but than I need to set this variable and use it all the time

var myGlobalVariable = new App();
    myGlobalVariable.interface.changeInterface();

and use it in a Class

class Interface(){
  constructor(){}

  changeInterface(){
    ...change interface...
    myGlobalVariable.App.Refresh(); // => call function from pre set
  }
}

Or maybe my thinking is wrong and I have to change it?

Thanks.