I think much of the confusion stems from the fact that we're discussing two somewhat similar ways to connect an "antenna" to the back of a desktop.
To further clarify what others have been also clarifying, I snapped this picture, just now, which shows two ways to connect an 'antenna' to the back of a typical desktop computer (aka "Ethernet" & "Wi-Fi"):
In the end analysis, while the costs are the same, the POWER is fantastically different, and yet, the result is your typical "Wi-Fi", which you can verify, for example, using your phone with freely available apps:
Notice that this desktop has both types of connections: a. There's a typically puny Wi-Fi "device" attached to this desktop b. There's a powerful Wi-Fi "device" attached to the desktop RJ45 port
Both cost about the same in terms of both price & setup (which is minimal). o But only one will be found at a typical consumer-focused box store.
One will get you distances of roughly a few hundred feed (or so). o While the other will garner distances easily of a few miles (or so).
Just to be clear for those who simply want us to explain tools more simply o For the price of what people already seem to pay for their home stuff o They can buy "this stuff" which easily connects to "your stuff"
Where "your stuff" includes anything you have in the house that o Connects to what we colloquially refer to as "Ethernet", or, o Connects to what we colloquially refer to as "Wi-Fi".
Where the main drawback of "this stuff" is o It's generally a bit larger (but not always) so you need shelf space o You definitely won't ever find "this stuff" in the normal box stores
So you simply have to KNOW that this kind of power is available to you. o And then you simply need advice on "what stuff" to purchase online
Where, the elegant beauty of "this stuff" is the sheer simplicity of it all o One end of "this stuff" is what we colloquially refer to as "Ethernet" o The other end is what we colloquially refer to as "Wi-Fi".
For example, here is a picture of "this stuff" showing both hose ends:
Notice the key colloquial takeaway to explain the immense power here: o One end attaches to ANYTHING you have that you'd call "Ethernet" o The other end attaches to ANYTHING else that you'd call "Wi-Fi"