JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/knockout/3.3.0/knockout-debug.js"></script>
<div>
    <p data-bind="text: MyArr()[0].check"></p>
</div>

JavaScript

function checking(obj)
{
    var self = this;    
    self.check = ko.observable(obj.count);
    alert(self.check());
};

function MyVM()
{
    var self = this;    
    self.MyArr = ko.observableArray();        
    var myObj = {count: 4};
    
    self.function1 = function(){

       self.MyArr.push(new checking(myObj));        
    };
    
    self.function1();

}

ko.applyBindings(new MyVM());