How do you ensure a WiFi connection for gaming?
Stay close to your internet source
Make sure you're as close to the WiFi signal antenna as possible. That's where the signal is strongest. With mesh routers, you can place WiFi stations throughout your house. This way, there's always a router near your PC or console. Isn't a mesh system a possibility? Choose a wired connection if there's a long distance between your gaming PC and your router. All you need in this case is a switch and network cables.
Give priority to your console with QoS
Prevent your brother or roommate from using up all the bandwidth downloading their favorite series. Adjust the QoS settings on your router. With quality of service, you give priority to the most important devices. Even when you game via the network cable, you can adjust the priority via QoS.
Game on the 5GHz band
The 2.4GHz band reaches the attic, but is very sensitive to interference. That's why you should play on the 5GHz band whenever possible. Preferably, with a WiFi 6 router or access point. These are best at transmitting a 5GHz connection. Currently, consoles don't work with the new 6GHz speed, but gaming laptops and desktops do.
Do you prefer to play in the attic?
Send the internet via a power or network cable to the top floor. Connect an access point via the network cable and create a WiFi hotspot. Because you send the internet signal through a wire, it won't weaken.