Google’s one-tap sign-up and automatic sign-in for mybb forum | PHP | javascript

Hi,

I am new to the php coding & development and just launched my community and wanted to integrate one tap google sign-in/Passwordless to my forum.
 

I want if anybody can help me with "callback response" and how to proceed further to save it at backend.

What I have tried:

<pre>I already embedded google login in registration & login page & have generated client id and secret key but wanted to setup automatic sign-in whenever as popup window on right : continue sign-in as...."