linking ip addresses

I have 5 public I.P. addresses. I would like to use one for a telephone, another for a camera and another for a server. How do I say for example use 43.78.127.37 (Sub 255.255.255.248 and gateway of 43.78.137.36) and point it to a camera on my network with a address of 192.168.10.25. Do I use port forwarding of something else… Please help and although not dumb; I’ll need some step by step help.