This might sound like a stupid question but I'm not tech savvy enough to know this!

I have a dual band gigabit wifi 6 router, and to improve my speeds and coverage around the house, I have just bought a tri-band wifi 7 mesh system. Given that the first mesh node needs to be plugged in to the router, will the mesh system be limited / restricted to the maximum that the route can output? Or does the router just act as a 'gateway' for the data to pass through to the mesh network which can then broadcast at whatever speeds it is capable of (subject to the incoming speeds from the fibre itself, and the port in the router that the mesh node is plugged in to)?