[Erolast]

fs.exists() is an anachronism and exists only for historical reasons. There should almost never be a reason to use it in your own code.

In particular, checking if a file exists before opening it is an anti-pattern that leaves you vulnerable to race conditions: another process may remove the file between the calls to fs.exists() and fs.open(). Just open the file and handle the error when it's not there.

//0777 и так дефолтный
fs.mkdir(path, (err) => {
    if (err) {
        console.log(`${path} already exists.`)
    }
})