Hidden page/URL

hi!
what’s the best way to set up a “hidden” page so everyine who knows the specific url link can access the page, but it won’t shiw up on google searches ect.
I want to set up a page to download a file just for people who know the url.

I found an article that tackles the issue here
but it’s from 2011. maybe there is a new feature or a plugun that would do the trick?
https://buildyourblog.net/content/create-hidden-page-wordpress

thanjs fir helping out!!
cheers
mika