I have the fibre optic cable on the main floor, and a router on the second floor of my villa. However, the wireless signal is very weak. Can I add a second router to the top floor?

Also I have heard the junction box can act as a wireless router but Ooredoo tech said he's not allowed to enable it. Does anyone know how to enable it?

As it stands right now I can only get workable Wireless on the second floor. The main floor and top floor are dead zones.

Thanks in advance.