Hey @Magdalena Michalak! Daniel from Customer Support Engineering here  

This isn’t something that’s currently supported in our articles product. You could potentially set up something like this with a DNS provider, but Intercom wouldn’t be able to provide steps on the setup. Alternatively, you could just include a space in your current articles to your new Help Center, but this wouldn’t automatically redirect like setting up a CNAME would.

Hope this is all clear!