Can't access the internet

I liked the post, because you correctly explained what happened and what went wrong.

Not kernel, but grub bootloader. This is not a Qubes-specific question, it’s related to Linux. Also was explained on this forum: one, two.

Indeed this is an important question. You can try to open Settings of sys-net, tab Devices and remove the currently attached device to it. Also check if it was the correct WiFi card. If not, you should try to attach the correct one. The qube should start without any devices attached (but you of course can’t have the Internet like this).