HI I want to add 2 mesh units to my stand alone deco x20-DSL router. add x20 or x60? My Internet connection is 1000Mbps / 250Mbps. will the mesh be faster if i add x60 units or because my router is x2

hello how to change user and password after changing my ISP on deco x20 DSL router? I dont want to reset the router

I want to have separate 2.4ghz and 5ghz wifi networks and also guest network. at the moment I activated the guest network as a 5GHZ network, but I want to run it regardless of the guest network. Is it