Starting Windows from HDMI/VGA on my broken Alienware Laptop

The screen on my old Laptop got a crack while we were moving and since the warranty is already gone, I have nothing to lose by taking the whole thing apart. I decided to make a media pc out of it.

The first hurdle I ran into is that I can't launch it from a secondary screen plugged in via HDMI. I kind of have to chose on the main screen that I want to operate a second output source after start-up.

Do I need a Laptop-to-HDMI adapter or can I change something in the BIOS menu or the NVIDIA control panel?

somehow I was not able to add fotos before.

this is not my final idea, it's just my test setup. The picture with the red mark is the current main visual output.

<3