You can't.
CWP isn't a router that can redirect different websites to different internal servers.
Each server needs to have a Public IP address for it's own webserver on port 80 & 443.
Now with NAT, you could redirect certain ports/services to certain internal IP's.
But again, you can NOT redirect the same port to multiple internal IP's.
If you want multiple servers, you have 2 options:
1. use servers on the cloud with Public IP's
2. ask your ISP if & how much a Static Public IP allocation would cost.
The local route would require you purchasing a router, firewall, switch, etc.
And the knowledge how to setup & configure it all.