Can I use K480 Logitech keyboard and wireless mouse with the new Mac mini?

Yes you can use most any keyboard and mouse with the new Mac mini.

The catch is, that you will need a USB keyboard and mouse to initially setup the new Mac mini, so that you can pare the Logitech wireless keyboard and mouse.

First of all, there’s no such thing as an iMac Mini. Do you mean M4 Mac Mini? There should be no problem with the wireless mouse. Make sure there’s a driver available for the Logitech mouse that’s compatible with macOS 15 Sequoia and Apple Silicon Macs.