Here is how to list the files/folders contained in a folder in the filesystem using Node.js:

const fs = require('fs')

const dir = '/Users/flavio/folder'
const files = fs.readdirSync(dir)

for (const file of files) {
  console.log(file)
}

Once you have a file reference, you can get its details using

const path = require('path')

//...

//inside the `for` loop
const stat = fs.lstatSync(path.join(dir, file))

This is useful to distinguish files from folders, for example, using the stat.isDirectory() method.

fs and path are built-in modules, no need to install them using npm