Just do exactly as you wrote yourself:
1) Create vlan-interface on top of port 2 with vlan-id=10
2) Create vlan-interface on top of port 3 with vlan-id=20
3) Assign addresses to this vlan-interfaces
4) Create DHCP servers on top of this vlan-interfaces
As a result the traffic on port2 and port3 will be tagged by corresponding vlan tag.
And you will have a dhcp running for each of the vlans.
Only note that 184.108.40.206 is not a private address, so in real setup it has to be something else from the private ip's range.