Calendar.jsx

....
import { AiOutlineLeft, AiOutlineRight } from "react-icons/ai";
import { format } from "date-fns";

const Calendar = () => {
....
  const getHeader = () => {
    return (
      <div class="header">
        <div className="todayButton">Today</div>
        <AiOutlineLeft className="navIcon" />
        <AiOutlineRight className="navIcon" />
        <h2 className="currentMonth">{format(activeDate, "MMMM yyyy")}</h2>
      </div>
    );
  };
....
}