First I have no experience of using Avast One, nor do I use Windows 11, so I have no practical experience here.
As far as I’m aware there is no way to recover your Avast One UI password, short of you having saved it somewhere outside of Avast.
For Avast Antivirus, Free or Premium for windows, I believe this would also be the case for Avast One. The only way around this is to run AvastClear from Safe mode, as trying to uninstall Avast whilst Windows is running would hit the Avast Self Defence module.
Now I don’t know if this option in your last WIN11 screenshot would be running Avast Clear from what would be Windows Safe Mode. If so, that should allow the Avast Clear to run and uninstall Avast whilst it isn’t running.
EDIT:
Ran a search for this and the AI Overview might help here.
clean reinstall of Avast One antivirus in Windows 11