JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://api.tiles.mapbox.com/mapbox.js/plugins/turf/v2.0.0/turf.min.js"></script>
<div id="res"></div>
<br>
<div id="res1"></div>

JavaScript

var pt = turf.point([1.0001, 1.0001]);

var poly = turf.polygon([
    [
        [-1, -1],
        [-1, 1],
        [1, 1],
        [1, -1],
        [-1, -1]
    ]
]);

var intersects = turf.intersect(poly, pt);

document.getElementById('res').innerHTML = 'Intersection between pt and poly: ' + !! intersects;

var buff = turf.buffer(poly, 500, 'meters');
var intersects1 = turf.intersect(buff.features[0].geometry, pt);

document.getElementById('res1').innerHTML = 'Intersection between pt and buffer: ' + !! intersects1;