Yes it is possible. But this includes a lot of manual work.
You can go to Advanced settings (luci) and try.
First need to go to network->interfaces and create guest-lan interface. You need static IP address e.g. 192.168.9.1 which should be different from the lan (192.168.8.1).
Then you need to go network -> wireless and create a 2nd AP interface and bind to your guest-lan.
Then you need to go network -> dhcp&dns and create guest-lan and bind to guest-lan interface for DHCP allocation.
Finally, you need to modify network->firewall and add your guest-lan to “lan” zone or create a new guest-lan zone.
Now your guest network is in a different zone as your own devices.
If you don’t mind your guests use the same network as your own network, then you can just create an AP interface in network->wireless and bind it to lan