OPNsense 20.1 Captive Portal config

[bdario]

Hello to all,
I'm looking for a howto regarding the configuration of the captive portal expecially the traffic shaping.
I found an old release doc (https://docs.opnsense.org/manual/how-tos/guestnet.html   Step 6 - Limit Guests Bandwidth) unapplicable to the 20.1 release.
Can someone help me?
Thank so much
Best regards
Dario