Sorry, just noted the title of the thread 
OK, since this is a C-7 hub, it doesn't have built-in WiFi. You will need an OTG cable and this adapter
https://www.amazon.com/gp/product/B0088TKTY2/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
If you can just connect the Hubitat hub to a network switch that is getting IP addresses assigned via DHCP, then just do that. But if it's for whatever reason impossible due to the setup you have, then here's the original post from the developer that wrote the code for adding WiFi to the C-5 and C-7 hubs.
