Your question lacks specificity. However, some time ago, I translated a Rust-based neural network into Fortran primarily using ChatGPT and manually correcting errors.
Given the improvement in this tool, ChatGPT may be your optimal choice. Nevertheless, if I were in your position, I would first modify the Python code to eliminate any external libraries.
Additionally, as pointed out by @nbehrnd, you might want to consider trying out neural-fortran. Unfortunately, my Fortran code is closed-source. Nevertheless, a few days ago, I initiated the development of a Lua-based deep learning program (view it here – it may contain bugs since the code is only several days old). Perhaps, having this in Fortran would be intriguing as well, but do we really need more options when neural-fortran is already well-established within the community?