Can I install Orbi pods with a Cox panaramic modem/router ?

Of course. People do it all the time.

Most of the time, having only a single router is a better overall solution than have two routers.

https://kb.netgear.com/30186/What-is-Double-NAT 

My preferred solution is to put the vendor's device into "bridge" or "passthrough" mode and use the Orbi as my router.

If changing the vendor's device is not possible, then putting the Orbi into Access Point (AP) mode can be useful.