How to use the tool for rate calculations

[shibo xu]

Hello, everyone:
I've been learning this tool recently and would like to be able to compute some rate-related content in biometabolic networks, but the official documentation searches for rate-related functions, and when I click on it, it shows 404, so which tutorial should I learn as a way to master calculating rates.
Moreover, I just started to learn about bioinformatics, and I feel confused about the concepts in the official documents, so I don't know where to start, and there are few other communication materials on the internet, how do you guys start to learn?

Thank you all!