I am wired with ethernet. I have never used Wi-Fi mainly because I am not familiar with it.
I don't know if you are using a laptop or a desktop but, in either case, you can access and use your Wi-Fi network in exactly the same way as your son did.
You look under the wi-fi symbol on your machine(top right corner of your screen) and you will see a list of wi-fi networks that your machine is picking up. Yours will be one of those and it will have a padlock beside it. That means the password is needed for you to join it.
If you are using a desktop, stick with the ethernet. That's what I use for my desktop too, whereas the iPads in the home and my daughters laptops when they visit all use the wi-fi.
If you are using a laptop you may wish to go with Wi-Fi as it will allow you to use your laptop anywhere in your home, rather than be constrained to the location of the ethernet cable.
