JSFiddle - React, Tailwind, and code Playground

HTML

<input id="firstName"></input>
<input id="lastName"></input>

JavaScript

$(document).ready(function() {
    $("#firstName").attr("data-bind", "value: firstName");
    $("#lastName").attr("data-bind", "value: lastName");
});

function AppViewModel() {
    this.firstName = "Bert"; //ko.observable("Bert");
    //this.lastName = "Bertington"; //ko.observable("Bertington");
}
ko.applyBindings(new AppViewModel());