But my laptop doesn't have a CD/DVD drive I can use to boot from W10 installation media. Is a USB flash drive applicable too?

Yet another update.

As I figured out that the cursor can move when I connected my bricked laptop to the TV thru HDMI, I tried to "blindly" log on to my laptop as I saw from another forum and tried...

An update...

So I tried connecting my laptop to a 2nd monitor (which is my TV) via HDMI and as soon as I connected it, the spinning dots paused and a BSOD appeared with a VIDEO DXGKRNL FATAL ERROR...

I have just upgraded my Lenovo Flex 2 from Windows 8.1 to Windows 10 with the ISO MS had provided in their site. Things were going smoothly until after reaching 75%, the laptop rebooted and voila, an...