I am unable to complete my HomePod set as the HomePod says it cannot connect using my wifi and that's the only wifi I have at home

see the Apple Support article If you can’t set up HomePod.

• HomePod uses the Wi-Fi network that your iOS or iPadOS device is connected to. Use your iOS or iPadOS device to forget the Wi-Fi network, then join the network again. 
• Personal Hotspots might work, but aren't recommended.
• If you're using an 802.1X Wi-Fi network, learn which networks are supported and how to connect to them. 
• HomePod doesn't support public or subscription networks with sign-in requirements. These networks are often in places like businesses, schools, dorms, apartments, hotels, and stores. 

Your Wi-Fi likely has client isolation or other Wi-Fi security protocol enabled that hides wireless clients from each other and the wired network. You need to turn this feature off.

tt2

You're welcome. 🙂

tt2