Question about AsRock B650I Lightning WiFi AM5 mITX HDMI DDR5 retail

If you see the drive while within the BIOS, but not in the installer, ensure the bios is in UEFI mode, and also try disabling CSM. Worst case you need to load storage drivers downloaded from AsRock site during install from a different USB, or copy them to the one you're using to install Windows.
Hope that helps.

As far as I'm concerned, it automatically recognises the M2 in the bios... on the other hand, I haven't yet found where to indicate the boot priority (ssd, ubs, etc) but as long as it's running I don't mind.

Does the bios recognise the M2? If not, either it's not connected properly or it's faulty.