JSFiddle - React, Tailwind, and code Playground

HTML

<input id="inputA" value="000" onchange="changeText()" />
<input id="inputB" value="" />

JavaScript

function changeText() {
   
    var A = document.getElementById('inputA').value;
    var B = document.getElementById('inputB');

    if (A != '000') { // or (A == '000')
        B.value = 'TextChanged';
    }
}