Error HA installation

Hello everybody,

I’m trying to instal HA using the following guide.
But during the step to acces my home assistant via http://homeassistant.local:8123
I get the following error message

This is my first time installing something on a raspberry pi, so I don’t got a lot of experience and would really appreciate your help! I’ve got a monitor attached to my pi, as well as a mouse and a keyboard.

The HA on my monitor looks like this (because I’m a new user I’m not allowed to upload more screenshots…):
Waiting for the Home Assistant CLI to be ready…
Home Assistant
Welcome to the Home Assistant command line.

Waiting for Supervisor to startup…
System information
IPv4 addresses for end0: 192.etc
IPv6 addresses for end0: 2001:etc.
IPv4 addresses for wlan0:

OS Version: Home Assistant OS 11.4
Home Assistant Core: landing page

Home Assistant URL: homeassistant.local:8123 (with http://)
Observer URL: homeassistant.local:4357 (with http://)
ha> _

The HA observer:4357 looks like this
Home Assistant observer
Supervisor: Connected
Supported: Supported
Healthy: Healthy

I really appreciate your help in getting this working! Thanks in advance for your time!