JSFiddle - React, Tailwind, and code Playground

HTML

<p>Try to type</p>
<div data-bind="foreach: users">
    <input type="text" data-bind="value: name, valueUpdate: 'afterkeydown', attr: { name: 'Users[' + $index() + ']' }" />
    <span data-bind="text: name"></span>
    </br>
</div>
<a href="#" data-bind="click: addUser">Add user</a>

<!--

If you submit such form, here is approppriate C# MVC model:

public class ViewModel
{
    public List<User> Users { get; set; }
}

public class User
{
    public string Name { get; set; }
}

-->

JavaScript

var viewModel = {
    users: ko.observableArray(),
    addUser: function() {
        this.users.push({ 
            name: ko.observable()
        });
    }
};

viewModel.addUser();

ko.applyBindings(viewModel);