@muralikanaga I would suggest access points or range extenders placed either next to a window, or outside. TP-Link sells both indoor and outdoor devices for network expansion. The outdoor devices would require some drilling to anchor the devices and create a wiring ingress (if your home doesn't have easy-access, exterior utility/wiring inlets), and devices that can provide "PoE" (Power over Ethernet).

  @muralikanaga 

Do not place the extender or MESH units to far from the main router. They need to be in a place where they get a good signal so it can pass the signal on.