JSFiddle - React, Tailwind, and code Playground

HTML

<a class="prev" href="#">Prev</a>
<a class="next" href="#">Next</a>

JavaScript

var arr = [1,2,3,4,5,6,7,8,9];
var batch = 2;
var num = 2;
var total = arr.length;
var group = arr.slice(0, (batch % total));


var add = function (amount) {
     num = (num + total - 1 + amount) % total + (2)
     console.log(arr.slice((num-batch), (num % total)))
}

$('a').click(function (e) {
    var num = e.target.className == 'prev' ? -1 : 1;
    add(num);
})

console.log(group)