CUDA and CUDNN installation

Hi everyone, when I put GPU 1070Ti to my computer (windows 10), I have not to install CUDA and CUDNN from these link:

https://developer.nvidia.com/rdp/cudnn-download
but when I run the code torch.cuda.is_available(), it is equivalent to True
Does that mean my computer installs CUDA and CUDNN automatically?
Thank you for your reading and I am looking forward to hearing advice from you!

No, it just means your system is CUDA-capable.
https://pytorch.org/docs/stable/cuda.html