JSFiddle - React, Tailwind, and code Playground
HTML
<form>
<input type="checkbox" name="detailsgiven" id="checkbox" checked=checked> Enabled?<br>
<input type='text' name="details" id="tb1" value='box1'><br>
<input type='text' name="details" id="tb2" value='box2'><br>
<input type='text' name="details" id="tb3" value='box3'><br>
</form>
JavaScript
var check = document.getElementById('checkbox');
check.addEventListener('click', toggleDisabled, false );
function toggleDisabled(evt) {
var checked = evt.target.checked;
if(checked){
document.getElementById('tb1').disabled = "disabled";
document.getElementById('tb2').disabled = "disabled";
document.getElementById('tb3').disabled = "disabled";
}else{
document.getElementById('tb1').disabled = "";
document.getElementById('tb2').disabled = "";
document.getElementById('tb3').disabled = "";
}
}