Connecting a laptop to Xfinity Hotspot

I know that the old style Xfinity hotspots were retired in Dec. 2023 (I think).  This past Friday, I took my wife to a medical appt., and brought my laptop with me.  The office did not have wifi, but I looked for connections and xfinity turned up as one of the hotspots detected.  I connected to it (didn't log in).  I tried the web, and after a few minutes a Xfinity web site popped up, telling me I had to sign up for something (don't remember what).  Anyway, how can I connect my laptop to xfinity when away from my house?

As a side note, this morning I was using my laptop, and it would only open certain web sites (couldn't go to any news sites).  I checked my connection and was surprised that I was connected to xfinity and not my locally generated private wifi signal from Xfinity.  I guess it was the xfinity generated from my modem (each modem generates two signals).  So I connected to my private wifi and that fixed the problem.

So what do I do to connect when away from my house (if an xfinity signal is available)?