Bubble web and Coded web connection

I was wondering,
can you connect an existing web with a web built on bubble.io?

For example,
let’s say I’m an intern for Reddit.
Reddit wants to launch and test a new feature called “A”.
“A” requires an independent page,
and I am planning to build the page “A” with Bubble.

In this case, are these possible?

  1. The User database of Reddit is connected to page “A”.
  2. When the User who is logged into Reddit moves to page “A”, he is still logged in.

Thank you all!

Yes, you’ll set up SSO connections for auth and use API calls to work with the data between both apps.

Thank you so much!!

Does this work with webs that don’t provide SNS logins, or provide multiple types of logins?
And is there an example of webs using this method for reference?

So with SSO,
the login process works basically alike to SNS logins?
Like when I login with Google for lots of platforms?