Step one: Create vlan and assign ports.
Switch(config)#vlan 10
Switch(config-vlan)#name tech
Switch(config-vlan)#exit
Switch(config)#vlan 20
Switch(config-vlan)#name sale
Switch(config-vlan)#exit
Switch(config)#int f0/10
Switch(config-if)#switchport mode access
Switch(config-if)#switchport access vlan 10
Switch(config-if)#exit
Switch(config)#int f0/20
Switch(config-if)#switchport mode access
Switch(config-if)#switchport access vlan 20
Switch(config-if)#exit
Step 2: Configure the switch cascade port as trunk.
Switch(config)#int f0/24
Switch(config-if)#switchport mode trunk
Switch(config-if)#exit
Step 3: Configure the router port and activate the port.
Router(config)#int f0/0
Router(config-if)#no shutdown
Router(config-if)#exit
Step 4: Configure the router subport and IP address.
Router(config)#int f0/0.10
Router(config-subif)#encapsulation dot1q 10
Router(config-subif)#ip add 192.168.10.1 255.255.255.0
Router(config-subif)#exit
Router(config)#int f0/0.20
Router(config-subif)#encapsulation dot1q 20
Router(config-subif)#ip add 192.168.20.1 255.255.255.0
Router(config-subif)#end
Step 5: View the routing table.
Router#show ip route
Step 6: Test the routing function between vlans
