These questions aren't well-suited on SO, but I'm posting a few resources you might start with anyway
The "Learning CUDA" section of the NVIDIA website is the best spot on resources and tutorials to get you up to speed: https://developer.nvidia.com/how-to-cuda-c-cpp
CUDA by Example(beginner) and Programming Massively Parallel Processors (intermediate) are also two good resources targeted to novices and intermediate CUDA users. There are lots more on the subject in the "Books" section of the NVIDIA website.
Once you got familiar with the basics of CUDA I recommend studying the CUDA SDK samples.
Regarding AI topics (I suppose "Network" means "Neural Network") there are some academic papers and lectures you might start with, but those would prove useless if you don't have a CUDA background first.