Welcome to the community !
I'd love to help. Kindly PM me your account details (username/customer ID or contact number associated with the account) I'll have this checked.
We can configure your modem/router without using Ethernet Cable as long as we have the Laptop connected via Wifi. What brand of modem/router do you have?
Usually, you can connect the laptop to the modem via cable or WiFi to configure it the first time, including setting up WiFi as you need. Thereafter WiFi should be available from the modem and so you can use your laptop anywhere it is in range.