Hello arthurfromowings mills,
From your post it appears that you are not able to sync your iPhone 8 with iTunes via Wi-Fi.
These are the steps that should be followed if using a Mac: Sync content between your Mac and iPhone or iPad over Wi-Fi - Apple Support
If you are using a Windows computer, be sure that you are following the steps outlined here: Sync iTunes content on PC with devices on Wi-Fi - Apple Support
If you continue to have an issue, be sure that the iPhone and the computer are connected to the same Wi-Fi network. Power cycle both the computer and the iPhone, along with all the network hardware such as modems or routers.
If the issue continues, then on the iPhone, tap on Settings > General > Transfer or Reset iPhone > Reset > Reset Network Settings. Also forget the network on the computer. Once these steps are complete, rejoin the network with both devices and test again.
Have a good day.