Hey Kamran,
Modern browsers can be set to prefer https or even to allow https exclusively (some are set this way by default).
The Raspberry Pi 3B that is inside the Onefinity Controller has WiFi capability, but the Onefinity Controller aluminium case acts as a faraday cage which shields the radio waves. Unlike other small single-board computers, the Raspberry Pi 3B has no external WiFi antenna socket.
Therefore using Ethernet is the good choice, also because a workshop is usually a place with many sources of EMI.
The Onefinity Controller is configured to do zeroconf address creation. This means, if you have a computer, a notebook or a tablet, you can connect it to the Onefinity Controller without having to configure the network connection. But if you have a DHCP server in a router (not a router ) in your LAN, this is another way to get an address automatically. Look at the router’s log to see if the Onefinity Controller appears there.
Are you using Windows version<10? If so, you may be interested in this: