This is correct. That appears to be a Zyxel GS-108S gigabit switch. The ports are QoS enabled: the green have highest traffic priority, yellow have medium, and gray low priority. This lets you arrange your network devices to ensure things like media streamers take priority over general web browsing, for instance.
This. If you’re not trying to use the wifi on the 2nd router, and it’s already wired to the 1st one, just replace it with a switch with the needed number of ports. Having a second router can definitely cause problems if the routing functions are still active.