Hello,
Yes, you just need to add additional WiFi interfaces in Network -> Wireless and then you will have multiple SSIDS.
To have them in different subnets, you would need to create additional network interfaces in Network -> Interfaces, and set it up in the same way as the original LAN interface, just have to set it up with a different subnet.
In the Wireless AP configuration as a network, you would need to set up as the new LAN interface you have created.