Fetch API を使用して GET リクエストにクエリ文字列パラメータを追加するにはどうすればよいですか?

http://myapi.com/orders?order_id=1

// Using URLSearchParams
var request = new Request({
  url: 'http://myapi.com/orders',
  method: 'GET'
});
var params = new URLSearchParams();
params.append('order_id', 1);
request.url += '?' + params.toString();

// Using URL
var request = new Request({
  url: new URL('http://myapi.com/orders'),
  method: 'GET'
});
request.url.searchParams.append('order_id', 1);

// Fetch comments for a specific post using URLSearchParams
async function fetchComments() {
  const postId = 1;
  const url = 'https://jsonplaceholder.typicode.com/comments?' +
    new URLSearchParams({ postId }).toString();
  const response = await fetch(url);
  const comments = await response.json();
  console.log(comments);
}

fetchComments();