networking – How do I hook up a business modem with 6 ports to a switched network?

I have a small business modem that has 6 ports on it, each being a static IP.

My network has grown however to the point where I have more than 6 devices, so I am moving to use a switch, which has other benefits as well.

Does that make my 6 static IPs redundant? Should I just connect one of them to the switch and NAT everything, or is there a way I can use all 6 IPs?