JSFiddle - React, Tailwind, and code Playground

HTML

<button onclick="calculate()">Test</button>

JavaScript

function calculate() {
       var firstNum = 1;
       var secondNum = 2;
       var list = [];
       for (var i = firstNum; i <= secondNum; i++) {
           list.push(i);
       }
       console.log(list);
   };