Wi-Fi

I have an Iphone 8 that does not allow the selection of Wifi. The sliding image remained in light grey signifying that the selection is not available. It is my backup phone and I have no sim card in it. This is the reason I upgraded. Non the less, I want this phone to work properly. I have completely reset the phone to new and in this process, the initial step of "Choose a Wifi Network" only allows a connection to a PC or Mac. And... I am in a rich environment for Wi-Fi

connection. What is the problem?