Daisy-chaining routers is can severely degrade some services (gaming, p2p) due to NAT. Assuming the ISP-provided one supports PCP or UPnP-IGD you need a client on your own router that relays port forwarding configuration to the upstream router. This is possible but may need non-trival setup.

PCP that allows ingress connections without an established egress connection is rarely enabled. The same applies to UPnP because of the baddies.

https://en.wikipedia.org/wiki/Port_Control_Protocol#Security