MVBM - Change Change Notifier

The idea is that what you would change the data, like I'm just trying to understand because but when I think about what I have in my mind is like you change the data on some model and then like everything's listening to it and it'll start updating. But that's not the way MVBM works, which is kind of, I believe you said it's kind of the backbone of what you guys started off as right? Okay. So, so you got this mostly from working with web applications such as Vue. And so the idea is that  what you would changed the data,like I'm just tried to understand because he was asking a little bit more explanation about how