IP addresses on Comcast business router

I have a comcast business router and the only thing behind it is an unmanaged switch. All of the IP addresses on my PCs are 192.168 but when I log into the router everything shows 10.0 addresses. I wanted to setup static IPs because I’m having some trouble on the network with printers but struggling with this IP addressing issue. I’m certainly not any sort of network wiz but I’ve done this on previous networks and not seen this dual addressing thing. What am I missing?