Membaca Value Form Input Type Radio Javascript

 1. Form

 <input type="radio" name="usia" value="Gen X">

  <input type="radio" name="usia" value="Gen Z">

  <button onclick="check()">check</button>

2. Javascript

function check(){

var usia = document.querySelector('[name=usia]:checked').value;

console.log(usia)

}