Interaction between back and front?

Question

Vue.js

I will describe the situation briefly. There is a form with users, and on the side there is a button that opens a modal with inf. users. The display is in inputs. Below is the save button. By clicking on this button, you need the form to update the values ​​\u200b\u200bthat have been changed. The information about users is taken from the back. The data is tied into the form. And with the change and subsequent preservation is difficult. Kowalski, options?