JSFiddle - React, Tailwind, and code Playground

HTML

<div id="datediv">
  
</div>

JavaScript

var dateDiv=document.getElementById('datediv')

function getDateOfWeek(w, y) {
  let date = new Date(y, 0, (1 + (w - 1) * 7)); // Elle's method
  date.setDate(date.getDate() + (1 - date.getDay())); // 0 - Sunday, 1 - Monday etc
  return date
}

var firstMonday  = getDateOfWeek(36,2021)
dateDiv.innerText=firstMonday