How to setup different password for guest profile?

If you read article in the search result for “how to secure your wifi” it talks about having a separate password for your guest profile. Which can be used for IoT devices or create a separate network for such devices, keeping it separate from your secure devices like phones/computers.
So that even if someone uses the IoT device to hack the network, your sensitive devices cannot be accessed.

How do I create a separate network on helix fi?

I read it gives an option to create diff password for 2.5 & 5GHz bands but that work around can impair device connectivity.