I am not using Google Cloud. I’m just using google account.
I need to login to some site with Google account, there are according option.
Sometime ago I registered successfully with Google account there.
Now I’m unable to login – when I press the button I’ve been redirected to the page, where it says

[Enter Google Account]
Access denied:         The OAuth client was deleted.
authentication error   If you are the developer of this app, read info about error.
                       Error 401: deleted_client
<and my email here>

Digging the web some suggests to enter Google Cloud, IAM & Admin, delete project, search for storages, clear them etc then recreate project, fill some paths, tokens etc.
But… the problem is I don’t know any paths, I have no scripts there to enter tokens etc, I just want to enter to someone others site, just as a regular user.
After what told to do, I have more problems that before I entered first time Google Cloud…

As a “regular user” I don’t need to know or do anything in Google Cloud – at blank google account this type of (OAuth) login to that site works ok, but not the account where I touched Google Cloud.
At new test google accounts when I go to console.cloud.google.com I see a message where Cloud says I can create new project. There are NO any projects, it’s clear, blank etc.

When I created project at my main email after some of that suggestions (made by google team too) then deleting (put to the deletion queue) project I suppose there are something broken and I don’t understand what broken and how to fix it.
My first tries to fix that was some time ago. Now I repeat to create new project, entered OAuth consent screen and found again (remembered) that it will not help, because “Edit app registration” (External) asks me for “app name” (I don’t know the app name asking OAuth because I’m not an owner of that external site, “application home page” – because the same. So it’s impossible to fix this 401 deleted_client with such steps.

I can’t move to new google account. This account is my main for nn years. There are some third party apps that works well, I tested some of them with logout-login by Google.
But some sites didn’t work and led me to 401 deleted_client and have no ideas how to fix that. There are no “reset Google Cloud” or similar or I can’t find it. New users has clear Google Cloud without any projects.

Anyone knows how to fix that? Thank you.