Google home - error setting up

I’m trying to set-up google home manually on Home assistant (not hass.io!) following these instructions :

everything goes well untill :

  1. Open the Google Home app and go into Account > Settings > Assistant > Home Control .
  2. Click the + sign, and near the bottom, you should have [test] your app name listed under ‘Add new.’ Selecting that should lead you to a browser to login your Home Assistant instance, then redirect back to a screen where you can set rooms for your devices or nicknames for your devices.

when I click on [test] Home Assistant it opens the browser but then I get the following error (see screenshot)

go back and double/triple check all of the settings, especially your HA URL’s make sure every character is there and not one step was skipped. There is a lot so chances are high something was skipped.

What I did notice was that I have to use https instead of http and my home assistant isn’t accesable through https, but in google home I cannot use http as a url (not accepted)

umm google assistant requires HTTPS, look at the warning at the top

Ah OK, so I first have to do this :

https://www.home-assistant.io/blog/2017/09/27/effortless-encryption-with-lets-encrypt-and-duckdns/

yea or something similar, needs to be externally accessible with SSL