1. You can insert tag script with lodash as source to your html file.

2. Using npm.

$ npm i -g npm
$ npm i --save lodash

3. In Node.js.

// Load the full build.
var _ = require('lodash');
// Load the core build.
var _ = require('lodash/core');
// Load the FP build for immutable auto-curried
iteratee-first data-last methods.
var fp = require('lodash/fp');
 
// Load method categories.
var array = require('lodash/array');
var object = require('lodash/fp/object');
 
// Cherry-pick methods for smaller
browserify/rollup/webpack bundles.
var at = require('lodash/at');
var curryN = require('lodash/fp/curryN');

function myChunk(arr, size = 1) {
	const output = [];
	for (let i = 0; i < arr.length; i += size ){
		let arrayChunk = arr.slice(i, i + size);
		output.push(arrayChunk);
	}
	return output;
}
 
myChunk(['a', 'b', 'c', 'd', 'e', 'f'], 2);
//--> [ [ 'a', 'b' ], [ 'c', 'd' ], [ 'e', 'f' ] ]
 
myChunk(['a', 'b', 'c', 'd', 'e'], 3);
//--> [ [ 'a', 'b', 'c' ], [ 'd', 'e' ] ]

	_.chunk(['a', 'b', 'c', 'd', 'e', 'f'], 2);
//-->[ [ 'a', 'b' ], [ 'c', 'd' ] ]
 
	_.chunk(['a', 'b', 'c', 'd', 'e'], 3);
//-->[ [ 'a', 'b', 'c' ], [ 'd', 'e' ] ]

function myCompact(arr) {
	const output = [];
	arr.forEach(element => {
		if (element) {
			output.push(element)
		}
	});
	return output;
}
myCompact([0, 1, false, 2, '', 3, NaN, null, undefined]);
//--> [ 1, 2, 3 ]

_.compact([0, 1, false, 2, '', 3, NaN, null, undefined]);
 
//--> [ 1, 2, 3 ]

function myIntersection(arr1, arr2) {
	return arr1.filter(x => arr2.includes(x));
}
 
let a = {b: 1}
let b = a
 
myIntersection([2, 1], [2, 3]);
//--> [2]
myIntersection([5, 2, 1, 4], [2, 3, 4, 5]);
//--> [ 5, 2, 4 ]
myIntersection([a], [b]);
//-->[ { b: 1 } ]

let a = {b: 1}
let b = a
 
_.intersection([2, 1], [2, 3]);
//--> [2]
_.intersection([5, 2, 1, 4], [2, 3, 4, 5]);
//--> [ 5, 2, 4 ]
_.intersection([a], [b]);
//-->[ { b: 1 } ]

function mySize(collection) {
	if (!Array.isArray(collection)) {
		return Object.keys(collection).length
	} else {
		return collection.length
	}
}
 
mySize([1, 2, 3]);
//--> 3
mySize({ 'a': 1, 'b': 2 });
//--> 2
mySize('pebbles');
//--> 7

_.size([1, 2, 3]);
//--> 3
 
_.size({ 'a': 1, 'b': 2 });
//--> 2
 
_.size('pebbles');
//--> 7