I don't think you understand what a Guest network is. To answer the question, most if not all of Xfinity's hardware does not support guest networks. Buy your own router.
Why do you have to make this so complicated. Simple question;
How do I set up a Guest network on my Xfinity home wifi?
My home wifi is a standard home wifi supplied by Xfinity. I have not asked 30 other questions. Just answer this one.
This didn't help?
Connect to Xfinity WiFi Home Hotspot
Many Xfinity Gateways broadcast a WiFi hotspot that can be accessed by guests who are Xfinity Internet customers. To connect to the Xfinity WiFi hotspot network, your guests can simply select the WiFi network labeled xfinitywifi or XFINITY on their devices. To learn more about Xfinity WiFi hotspots, visit wifi.xfinity.com .?"
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