In working level, How do I convert pyotrch to C++

Hi guys, I’m looking for a job, so I’m practicing converting PyTorch to C++. I wonder how to convert PyTorch at a working level. I found methods like TorchScript, LibTorch, and ONNX, but I don’t know which one to use.
I want to know what to practice
I need to know when to use each method.

Thank you for reading!