USB Hub & Mac Mini M2

Yes you can.

You can use a USB-A hub connected to one of the two USB-A ports.

Or you can use a USB-C hub connected to one of the 2 Thunderbolt 4/USB-C ports.

You use should use a Self-Powered hub, if you are connecting multiply bus powered drives and other devices to the hub.

That is not good nor right.

You should be able to hot plug a good USB cable or device into the Mac mini.

At this point, you should take it to your local Apple Store or AASP and have it looked at.

Keep in mind that if you have had it for less than 14 days, you can return it no questions asked.

You're welcome.

What USB devices are you wanting to connect to the new Mac mini?

An external USB-A drive or other device can be connected to one of the USB-C ports using a USB-C to USB-A adapter.

The Apple adapter.

USB-C to USB Adapter - Apple

Or third party USB-C to USB-A adapters.

https://www.amazon.com/dp/B0B9N3QSL3/ref=sspa_dk_detail_0?

https://www.target.com/p/philips-usb-c-to-3-0-usb-a-female-adapter/-/A-79804275

You're welcome.