Which files render the Login/Register Page

Hi.
We are using OJS 3.3.0.17 (PHP version 7.4.33). Our site is https://journals.du.ac.bd.

We are hosting 20 journals. We have just enabled Google OpenID Connect. After that both the Register and Login page of the site homepage shows “Incorrect OpenID plugin configuration!”. However, the Register/Login pages of all journals are working fine. In reality, the OpenID Authentication Plugin does not offer a ‘settings’ option for the main site, but offers that for all journal pages. So, we were able to provide login credentials only for the journal pages, but not for the main page.

So, I would like to customize the message of Login/Register page of the main site. However, I could not locate the file that renders these pages.

I checked the tpl files in /pkp/templates/frontend/components/ folder. I also check the tpl files in lib/pkp/templates/frontend/pages/ folder. I tried to paste a test line such as

Testing

in different tpl files in those two folders, but the line does not appear in the login/register page.

Could anyone tell me the location and name of the file(s) where the message such as " Sign in or register" is written?

Moreover, any suggestion on how we can set login credentials for Google OpenID connect for the site’s homepage?

Thanks.
Asif