MVVM pattern - public methods and properties meant only for the View

With the MVVM pattern, I make the methods and properties the View binds to as public.

It feels like these should only be public for the view, and not anywhere else. Almost like a protected concept. But also, you want some public methods that can be used by other classes, so it gets kind of muddled.

I'm writing TypeScript so I could really access whatever methods/properties I wanted to, but in a language like C# I would guess you would have to expose viewodel properties as public for the view and truly have this issue.

ViewModel:

class viewModel {
  private mode = "Editable";
  // this is only meant for the view. but it's public so it could be tampered with.
  public items = ko.observableArray();
  // this is meant to be used by other code.
  public setMode(mode) {
    this.mode = mode;
  }
  private _datasvc = new someDataService();
  constructor() {
    this.items = this._datsvc.getItems();
  }
}

Am I just not understanding or using MVVM correctly?