Access files config files and log from CLI

After I run a update and it reboot my Home Assistant OS 9.0 I have no access from webpage.
It just say “Unable to connect to Home Assistant retrying…”

I have access from Home Assistant command line but I have no idea how I can access the log file to see what error I have or config file to change settings.

/Update
I have not got it to work again.
I did have a config backup that run everynight to my nextcloud so I did download the config and did see the username and password to SSH that I have install
After that I run WinSCP to access the file and edit my config and restart.