You need to convert the date to iso string and get first 10 characters.
e.g.
var curr = new Date();
curr.setDate(curr.getDate() + 3);
var date = curr.toISOString().substring(0,10);
<input id="dateRequired" type="date" name="dateRequired" defaultValue={date} /> Reference toISOString method.
Also you can see the result here