I want to create this lab to apply the rules of iptables on the network,how I selected IP addresses for each interface and each sub-networks to create this lab please help me enter image description here
Link Internet: This will more than likely be DHCP'ed from your router. If not you will need a 'local IP' and set the gateway to the internet.
Link Teachers: a 192.168.x.x subnet will do the trick. as this is a lab, you could use 192.168.1.x/24
Link DMZ: Same as Teachers link use 192.168.2.x/24
Link Students: Same as Teachers Link use 192.168.3.x/24
Of course if you have more than 254 devices on the subnet, then you will need to increase the range.
If you only have 1 network card, then you will need to bind an IP address from each subnet to the network card - binding multiple IPs source.
Once you have your interfaces and networks setup, you should be able use IPTABLES.