If you want to receive an email after each user registration, you just need to go to "Dashboard > wpForo > Settings > Email Settings > New User Registration Email for Administrators" and then disable the "Stop Sending Emails to Admins on New User Registration" option.
For more information on shortcodes in email templates, you can refer to the documentation link I have attached.

https://wpforo.com/community/postid/68337/

Is there a solution such that an admin receives automatic email of the user who's requesting to sign up or a google sheets solution that automaticaly updates every time a registration is requested?

Also if the registration had custom fields like First Name, Last Name, etc. which information filled in also gets sent in the email

Is it possible to send the admin an automatic email that someone requested to register? Currently the user has to write a message in that box, then click send for the email to come but i would like it to be automated.

And if possible, automatically put onto a google sheets (email of user requesting registration with date+time they requested registatration)

Thank you