wifi

I can get internet on my phone and chromebook in other parts of the house yet I saw where wifi is not enabled or connected.
Is that because the gateway's router is giving off the wifi signal?
It seems odd to me that wifi is off in my desktop settings yet the house's network is getting it.
Should I turn it on or off at my desktop if I want other rooms within my network to receive wifi securely?
My desktop is connected to the gateway with an ethernet cable.My printer is connected to the gateway with and ethernet cable too but wifi is not enabled yet it too responds to devices from other rooms.
I obviously do not understand the concept of networking at my level.

If the wifi is on at the router then its on if you cant get it in some room does it not show when you search if not you are out of range

Everything is fine. I just do not know why I get wifi at a device if the desktop is set to no wifi. It must be the router sending the signal.
Why is there a "wifi off" at the desktop if wifi is on throughout the house?

The desktop doesnt send out wifi it all comes from the router turning wifi on at the desktop just means it can then recieve wifi it doesnt effect any other device

"Is that because the gateway's router is giving off the wifi signal?"
Yes, The Wireless Access Point is in what people call a "Gateway" or "Router".

Each device is connected to that separately.
To turn off the WiFi completely you turn the Wireless Access Point off in the "Router/Gateway".

Each individual device can have it's WiFi off, or you can connect with an Ethernet cable like your Printer and Desktop.

That's why it's called a "router", part of it's job is routing stuff to/from wired and wired devices on your network.

Some devices will connect directly by WiFi to say the printer(WiFi direct). In that case the Wireless Access point in the Router is not used.

Could also be that it's only the last few years that some computer makers or vendors are including Wi-Fi capability with the Network adapter and if using Ethernet connection to the Router shouldn't also need Wi-Fi on a Desktop. My year-old ASUS Desktop came with an add-in Wi-Fi card [which included Bluetooth Wireless], since I used the able connection I unplugged the card in favor of a 4-port PCI3-X1 USB 3.0 add-in card.

Turning wifi on at the desktop would then enable wifi for it if it has a card which it does not. It then could receive the wifi signal.
The router in the gateway is what is connecting the other devices to the web and the desktop is connected to the internet by the ethernet cable.
So all except the ethernet cable is wifi connecting my phones and chromebook.
I may have put it a bit wrong but I understand and thank you all.