Why does CUDA work for Intel?

Question

Windows

I installed WSL on Windows 10 Arch Linux, then I decided to test the code that translates speech into a test using Mozilla DeepSpeech, the code didn’t run at first, then I installed cuda 10.1 and the code worked.
Questions:
1) How could cuda be installed via WSL if WSL does not have access to the hardware?
2) How was cuda installed if I have Intel HD Graphics?
3) Why did it all, in general, start up and work (by the way, in the DeepSpeech documentation , in general, it is written that

if you're using Linux and have a supported NVIDIA GPU, you can install the GPU specific package as follows:

)?!

Answer 1

Perhaps in emulation mode on the CPU?
p.s. https://developer.nvidia.com/cuda/wsl

Answer 2

If it worked exclusively on CUDA, then the third point would look different.